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Garmin Nuvi 300: a motorist's marriage-saver?

Last modified: Thu Apr 17 12:16:31 2008

``Turn left here.''
``OK.''
``No not here!''
``You said left!''
``No I didn't!''
``Yes you did!''
``Alright, but you should have realized I meant right.''
``You said left!''
``You should have known I meant right -- this is somebody's front yard. Would I direct us into somebody's front yard?''
``I don't know. You might, if you were in that kind of mood.''
``I wouldn't be in `that kind of mood' if you ever took any notice of what I said.''
``I would take more notice of what you said if you didn't say `left' when you meant `right'!

Uh-oh... this conversation is rapidly heading in the direction of what your brother's wife said about my haircut at our Neville's wedding, and we all know where that one ends.

I should point out from the outset that the Nuvi 300 won't nag you less than your spouse. On the contrary: its infuriatingly calm, persistently intrusive voice drives me up the wall. But, unlike your spouse, when it says `turn left', it actually means `left', not `right'. But is its right right? Or will it have you going nowhere, like your ill-fated relationship?

I bought the Nuvi 300 after an extensive period of research. That is, I researched the price labels on the shelves at the local Comet, and it was the cheapest. Less than a hundred quid for a unit that includes street-level mapping of the whole of the UK, and is the size of a pack of playing cards. That can't be bad. To be sure, alongside the price label there was a whole heap of information about POIs and WAIS and TFT and whatnot, but who knows what that means? But `Special Offer' -- that I can understand.

Does it work?

Basically, yes. The little box suction-mounts to your windscreen (or clamps to your bicycle -- more on this later) and is powered from your vehicle's ciggie-lighter socket. If you haven't got a ciggie lighter you could be in trouble, but the Nuvi has an internal battery which seems to be good for about four hours' operation. So you could, at a pinch, charge it at home. No mains charger is included in the basic package, but it charges over USB so plugging it into a computer should do the trick.
      The Nuvi takes about half a minute to establish your location, perhaps a bit less if you haven't moved since you last used it. Then you can ask it to take you to a particular postcode, or address, or grid reference. Once underway the unit shouts out directions of the form `Drive five hundred feet then enter roundabout'. It also displays the route in a sort of perspective view which, for me at least, works surprisingly well. If you go the wrong way (whether it's your fault or the Nuvi's -- and it does make mistakes) it calmly calls out ``Recalculating'' and figures out a new route. For nine journeys out of ten it's a wholly painless experience, and far better than alimony. The first time I used it on one of my regular journeys, it reduced what had always been a fifty-mile route to a thirty-mile one, simply by finding a route that I'd never have been able to navigate with a paper map. I'll have more to say about the one journey out of ten that doesn't go according to plan later.

As well as navigation, the Nuvi can play MP3 audio files and, with optional software, does language translation and some other travel-oriented stuff. It can also warn about speed cameras, which is a mixed blessing -- more later. There is an interface for an optional FM traffic information receiver which I haven't tried, so won't be saying anything about.

Routing considerations

Compared to PC-based road routing applications, the Nuvi's routing algorithm -- whilst it nearly always works -- seems pretty crude. In essence you have a choice of `fastest' or `quickest' route. You can tell it to avoid U-turns and `highways', although it isn't entirely clear what a highway is. There is an off-road routing option as well, although I haven't really had much opportunity to try it.
      The problem with navigation by the `quickest route' strategy is that the algorithm doesn't really have any reliable way to know the speeds that can be maintained on particular roads. This isn't a limitation of the Nuvi in particular, but sophisticated routing applications usually allow the user to enter real speed data for particular roads, and have that data used in the computation. I'm not aware of any self-contained unit that can do this, so the Nuvi doesn't really fare worse than the competition in this respect.
      But what some units can do, and the Nuvi can't, is to assign preferential weightings to particular classes of road. So you might be able to configure a unit to favour `A' roads at the expense of smaller roads, even if that makes the journey longer. Lacking this feature, the Nuvi does have a tendency to send you down single-track roads in regions where they predominate. I noticed this particularly in Devon, which seems to have about ten times more singletrack than anything else. Now, very often, using roads like this actually is quicker. That's particularly true in Devon and Cornwall (and, I presume, other rural areas that attract a lot of tourists) because the few highways are often clogged with traffic. But even in more urban areas, the Nuvi seems to make an assumption that you can drive at 30mph wherever that is the legal speed limit -- an assumption which is often unwarranted.
      The problem with the `shortest route' strategy is that it tends to use small roads that are fiddly to negotiate. Of course, if you ask for the shortest route, it's hardly the fault of the navigator if the shortest route happens to be inconvenient. But it would be nice to have routing options of the form `shortest route avoiding singletrack' and `shortest route avoiding town centres'.
      But I think the most irksome problem with the routing is that the Nuvi seems to assume that a turn can be made in negligible time. So in both `fastest' and `shortest' routing modes, if the roads in an area will all carry traffic it the same nominal speed, the Nuvi will tend to select the shortest route even if it has many turns. It's sent me down narrow roads between shops, for example, to shave a few yards off the distance.
      This probably all sounds very negative but, in fact, in nearly all cases I have set the Nuvi to `fastest route' when driving and `shortest route' when cycling, and it's worked perfectly well. It's never sent me into a dead end, or down a muddy bridleway, or the wrong way up a one-way street. It has, on one occasion, asked me to turn in a direction that was forbidden by the road markings; but it recovered quickly enough once it realized I was heading the `wrong' way. An aside: the Nuvi does not realize that you can, and sometimes must, go around the Plough (`Magic') Roundabout in Hemel Hempstead anticlockwise. The poor old thing was completely baffled by this -- you could tell it was upset. But I suppose it's asking a lot for a pocket-sized navigator to cope with completely abberant road layouts like this.

One thing the Nuvi lacks, and which is less excusable, is a facility to avoid particular roads altogether. When driving I often find that traffic is painfully slow, perhaps almost stationary, on certain roads. Some roads, of course, are like that all the time. If the Nuvi decides that the best route for you is along the Dogpatch Bypass, it will jolly well make you drive that way, whether you like it or not. There is a `detour' facility, which is supposed to make the unit calculate an alternative route. However, there is nothing to stop the unit routing you off a troublesome road and then back on it a hundred yards later.
      The most extreme, and maddening, example of this I have so far encoutered took place on the M25. Traffic was very slow, and I pressed the `detour' button in the hope that I would be routed off the motorway. I was -- but the Nuvi send me off the M25 and then immediately back on at the other side of the intersection. Now, a human navigator may well make mistakes, but I don't think any human being would think that this was a sensible route choice.

In summary, the Nuvi's routing algorithm works pretty well in light traffic, when you can actually follow the route it has worked out. But it offers little flexibility if conditions are less appealing. In addition, you can't plan a route in advance (using, say, a PC-based routing application) and then transfer it to the Nuvi and have it use it. The best you can do is to insert one `via point' in the route, and this is really only useful for things like fuel stops.

Calculating the route is one thing -- being able to follow it is another. The Nuvi does give voice directions, but it also displays a map and, in very tortuous road layouts, you'll need to refer to the map. Where there are many twists and turns very close together, it simply can't speak the directions quickly enough. By the time it's said `Exit left and then enter rounabout' you might have entered and exited the next roundabout. As always, the unit recovers pretty well from this kind of situation, but it's best to glance at the map when approaching an area where there are roundabouts on top of one another.

User interface

The Nuvi uses a touchscreen for all user input -- the only mechanical switch is the power button. The power button also brings up the volume and brightness controls on screen, which is quite convenient compared to finding them on a menu. The screen itself has a high contrast and, with the backlight on, is visible even in direct sunlight.
      Garmin has done a pretty good job of making use of the available area of the small screen. More expensive models have bigger screens but are, of course, less pocketable as a result. Most of the on-screen buttons for data entry are big enough to prod cleanly with my fat fingers, but I struggle a bit when entering alphanumeric data (e.g., postcodes). To get a whole alphabet's worth of buttons on screen does make each button a bit tiddly, particularly if your fingers are sausage-shaped. One minor gripe -- I would prefer the on-screen ABCDE... keyboard to have a QWERTY layout, at least as an option.
      But, on the whole, the user interface seems to me to be about as intuitively obvious as it can possibly be. The only difficulty I have had is saving my current location with a particular name for future reference. Even now, without the unit in front of me, I can't remember how to do this -- it is not at all obvious. To get to the MP3 player, you have to chose `Travel Kit' from the main menu, which is also not particular obvious, but I'm really picking at nits here.
      Clearly Garmin have put some effort into figuring out how this unit will actually be used, and doing a lot of stuff without user intervention. A nice touch, for example, is that the display has `day' and `night' colour schemes -- bright colours with high contrast for daytime use, and darker, more subdued colouring to be less intrusive at night. The Nuvi can switch between the two modes automatically, although I'm not sure how it does so. It isn't based on the actual light level, so I assume it's based on time-of-day.

I've mostly used the Nuvi with the perspective map displayed, although there are other display modes. The perspective mode shows the road layout as it would be seen (approximately) by the driver, so distant roads appear smaller, as they do in reality. As you turn, the display updates so that you're always seeing the `front view'. Actually, the display lags reality by a second or two, which is sometimes a bit of a nuisance. Partly, I think, this is because the unit doesn't have enough CPU oomph to draw the map any quicker, but GPS itself is probably a limitation as well. GPS is not a particularly good way to determine orientation, as opposed to position.
      You can zoom and pan the perspective map, although it isn't particularly quick in operation. There is a trade-off between map detail and display speed, as you might expect. I like the map to be finely detailed, but this does make it slower to update. It's worth bearing in mind that the Nuvi map shows only roads, railways, major bodies of water, and certain points of interest from its database. It is of very limited use for off-road situations, as the map does not show small tracks, buildings, contours, rights of way, or geophysical features in general. Of course, Garmin sell more specialised navigation devices for these kinds of application. I find it really irskome that the Nuvi won't tell me my location as a grid reference, which is something I often need when cycling off-road with a map, but that isn't really the unit's intended application, I guess.

Apart from features which we can't reasonably expect in a device of this sort, what does the user interface lack? Most obviously, for me at least, is that there is no convenient way to preview the whole route. In a sense it wouldn't be particularly useful, since you get almost no control over the route it has chosen. But it would be nice to ensure at a glance that it isn't sending you on a totally mad route (although it hasn't, so far). It would be nice, I think, if the other information displayed on the map view (apart from the map) were configurable. For example, I would like to be able to display the current time of day rather than, say, the speed (I've got a speedometer for that).

Finding places

I've already described the Nuvi's routing capabilities -- the good and the not-so-good -- but routing is really only half the job of navigation. You also need a way to specify where it is that you want to end up. The Nuvi offers essentially three ways to do this: by address, by postcode, and by grid reference. There's also a database of places of interest, of which more later.
      Nine times out of ten, navigation to a particular premises can be accomplished by postcode/house number combination. In this mode, when it works, navigation really is door to door. The unit will get you to within about 30ft of a particular address. On the other one occasion out of ten, postcode naviation fails completely, either at the beginning of the route or the end of it. Now, it's never put me in Glasgow when I wanted Watford, but its postcodes have been wrong by more than a few hundred yards. On some occasions I've looked into this, and it's turned out that there is real confusion about the postcode even in the local area -- perhaps postcodes have been reallocated to make room for new houses or something of that sort. It's rarely been badly wrong, and perhaps the fact that it is so often so accurate make it all the more irritating on the few occasions when it isn't.
      I've also noticed, on occasion, that the unit finds a postcode in its database with no corresponding address. Usually when you enter a postcode it will tell you the corresponding city and street. If it doesn't do that, then I am suspicious about whether it will find the right place. In fact, I haven't tried it -- on such occasions I fall back on entering the address.
      So far, the Nuvi has never incorrectly placed a location that I specified by address. When you can use it, this is by far the most robust method of destination selection, besides entering an explicit grid reference. Sometimes you can't use it, as many places don't have addresses of the form number/street/city. But even then you can usually get pretty close by giving the street name (or road number) and picking a house number at random.

The Nuvi has a very extensive database of `places of interest', about which I have mixed feelings. It works very well when what you want is to find the nearest premises of a particular type. For example, if you want the nearest filling station (and I use this all the time), or the nearest hospital (not so far, thankfully), or the nearest food shop, it works pretty well. The Nuvi will find filling stations in the most obscure places -- places you'd never find by driving around aimlessly on the last few drops of fuel. In fact, because I drive a lot in unfamiliar places, the ability to locate filling stations alone is worth the price of the Nuvi.
      Where the database performs less well is in finding a specific place, rather than any place of a particular kind. I rather suspect that its database is a few years behind events. I know of two really huge supermarkets that it doesn't list, both of which were built about three years ago. But, in other cases it seems that the database compilers have simply been a bit arbitrary in their choice what to include.

MP3 player

The Nuvi has a rudimentary MP3 player, which can play files from an SD card. You can store data on the card from the unit itself when it is plugged into a host computer by the USB cable, or using a separate card writer. I don't know exactly what capacity SD cards the Nuvi can use -- 1Gb was OK, 4Gb was not; but maybe a different brand of 4Gb card would have worked. To be honest, there's not much point in using cards larger than 1Gb or so, as the unit's ability to organize and select files is so limited. The sound quality is pretty fair through the audio output jack, and the unit has the good sense to mute MP3 playback when giving travel directions. In a car, the MP3 player is really only useful if you have a way to connect its audio output to a proper car audio system -- you wouldn't want to listen to music on the Nuvi's built in speaker for very long. But I use the MP3 player on my bicycle all the time, as I have to wear earphones for the traffic directions anyway.

Speed cameras

The Nuvi has the ability to warn of nearby speed cameras (or `safety cameras' as it insists on calling them). This mode of operation certainly encourages slower driving, at least around the cameras, because the Nuvi bongs constantly and intrusively whenever you exceed the speed limit in the area of a camera. I've found myself slowing down just to avoid the nagging.
      But I think there's a risk that a driver could become too dependent on speed camera warnings, and not pay much attention to overall speed limits, let alone to the presence of the actual yellow boxes by the roadside. Not only would this be bad for road safety, if you don't keep the speed camera database scrupulously up-to-date you run the risk of getting nicked when you pass a camera that isn't in the database. Of course, these considerations apply to any speed camera warning system, not just to the Nuvi.
      Keeping the datbase up-to-date requires a subscription -- which is inexpensive enough not to be problematic for most people -- and the self-discipline to do the update regularly -- which is more of a problem. Garmin has a web-based updating system, and I was very surprised to find that it worked with my Linux-based PC (things like this usually don't). Nevertheless, I'm not sure I will renew my subscription, because I am less than certain that it improves my driving. Moreover, if I upgraded my GPS unit, even to another one in the same range, I don't know if it would be possible to transfer my subscription to the new device. Garmin is pretty vague on this point.

Cycling

Navigation is more of a problem for me on my bicycle than in a car. Not only am I more likely to cycle in places with which I am unfamiliar than to drive, but getting lost on a bike is somehow more tiresome than in a car. I'm not sure why -- perhaps because I cycle predominantly for pleasure, while I only drive from necessity. Anyway, I've started using the Nuvi on my bike, and it works reasonably well, so long as you keep its limitations in mind.
      Although the Nuvi 300 is advertised as suitable for cycling, and even has a bicycle routing mode (more later), Garmin don't sell a handlebar mounting bracket for it. Quite how they expect cyclists to use it, I don't know. I think, in reality, they don't expect cyclists to use it -- if they did, they would make it waterproof. But in that case they ought not to claim that it is suitable for cycling. In any event, Ram make a specific handlebar mount for the Nuvi. Ram products aren't particular easy to get in the UK, but I was able to get one from an on-line retailer in the US for not much more than the cost of postage. The Ram bracket is heavy, and not very elegant, but it holds the Nuvi quite firmly, and it doesn't rattle. There is no way to attach a lanyard to the Nuvi -- again unlike the Garmin products that are really designed for outdoor use -- so I wouldn't use the Nuvi for cycling offroad, as I'd be worried it would be bounced onto the grond. But since it's not much good for off-road use anyway, that's not really a big deal.

You probably shouldn't fiddle with the controls on the Nuvi when you're riding a bike, any more than you should when driving a car. But, if you do, the big on-screen buttons make it relatively easy to operate even when bouncing along. I've found that the best way to operate it is by poking the screen with my thumb, resting the rest of my fingers on the top of the unit.

But does it work? Well, at a plain technological level it certainly works. I was concerned that the comparatively low speed of a bicycle would make it difficult for the unit to determine your heading (I don't think the Nuvi has a proper electronic compass, so it relies on differential position to determine heading). But in fact is seems OK, except that when you turn a corner it takes quite a while for the map to update to your new orientation.
      The problem is that the Nuvi doesn't really have any concept of a bike-friendly road. Although it does have a bicycle routing mode, my experience so far is that its routing is the same for a bicycle as it is for a car if you enable the `avoid highways' mode. Of course, for a bicycle you can realistically use the `shortest route' naviation mode, which is often impractical in a car. But what would have been nice, in my view, is a routing mode that favours minor roads. Even better would be a facility to define a route outside the unit and upload it; but that feature is completely lacking.

Why spend more?

The Nuvi 300 is pretty much at the bottom of Garmin's vehicle-oriented navigation product range, and it's worth thinking about what you might get if you spend a bit more and go for a more up-range model.

• Bigger screen (at the expense of portability, of course)
• FM transmitter (to broadcast audio to a car radio -- sometimes works, sometimes doesn't)
• Spoken street names (`Turn left into Accacia Avenue' rather than `Turn left in 50 feet')
• Bluetooth interface and hands-free mobile phone support
• Built-in traffic receiver (optional on the Nuvi 300)
• More flexible route planning, including multiple via points and user-defined routes
• Wider map coverage (the UK Nuvi 300 includes only UK maps)
• More sophisticated vehicle mounting options

All well and good, no doubt. But, so far as I can tell, none of the Garmin range offers the features which the 300 lacks and which I find most necessary: an ability to avoid particular roads or road sections, and an ability to favour minor roads. These features are available in other vendor's products, however (note to Garmin!)

Conclusion

The Nuvi 300 was undoubtedly a good purchase for the price. It's worth reflecting on how incredible this kind of technology is, and how inconceivable it would have been even fifty years ago. At that time, a hand-held system that contained a database of every road in the UK, and could calculate routes as you drive, would have been beyond the imagination even of a science fiction author. Given that, it seems almost churlish to complain when your GPS unit navigates you from one end of the country to another, and you end up 50 yards from where you wanted to be.
      And yet people do complain. I've had people tell me that they wouldn't trust a sat-nav unit because they've heard how some truck driver was led down a farm track, or something. To which the response must surely be: So? Do you expect to be driving a truck any time soon?
      I think GPS navigation, in this sense, is a victim of its own success. It's so impressive, that people complain when it isn't actually perfect. And it isn't perfect: The Nuvi 300 has sometimes picked routes that I would not have chosen, and it doesn't help you much if you don't like its route. It's places-of-interest database is not exhaustive, and even its post-codes aren't always spot-on.
      But nobody ever said that having a sat-nav unit meant you didn't have to exercise any intelligence. The Nuvi 300 works pretty well most of the time. At under a hundred quid it really can't be said to be poor value for money, despite its limitations.

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