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Unusually for a PND– perhaps even, uniquely – the 3790T has an accelerometer so it can be used in portrait or landscape. The windscreen bracket is a ball and socket affair that lets you turn the between the two in-situ.

Slimphone pocketability in evidence here
Garmin doesn't quote a battery capacity but says a full charge is good for four hours of use which is more than twice what I would expect from a run-of-the-mill PND. The best I managed was just shy of three with the Bluetooth radio on, but that's still pretty impressive.

Main menu
Alas, the 3790T's navigational ability doesn't match its looks. The basics were fine, but map re-orientation was often slow and sometimes fluctuated badly during direction changes, leaving me confused as to my intended direction of travel, until the graphics settled down a few hundred yards along the road.

So there I was...
This was exacerbated by an occasional tendency to show the location icon to the left or right of the road I was on. This screen grab demonstrates the problem. At the time I was actually driving down Folly Lane which can be seen on the right of the image.

3D views of local terrain
Garmin's belief that road numbers should be read-out as hundreds and thousands didn't endear me to the 3790T either – admittedly a matter of personal taste. No arguments about the maps though, which are easy to read and come complete with 3D representations of terrain, city blocks and significant buildings.
COMMENTS
@Garmin: Accuracy long way to go & Warranty - OK if you like a fight
I have a Garmin (somewhere - I switched to an HTC with Google maps) and it was very bad.
A warranty fix cost me $43 (the case let water in), it was slow to resolve locations and sucked batteries.
AVOID THEM if you want piece of mind!
Garmin: Accuracy long way to go & Warranty - OK if you like a fight
Sorry, I've a number of different products and Garmin has poor accuracy.
A good GPS needs a good antenna - not something subverted for the primacy of appearance or form. Good GPS have external antennae, power and data connections.
As for Garmin's warranty, it's pathetic. If you travel to different regions of the world you will only get free warranty support from the regional office where you bought the unit.
Maps are so critical to GPS usability. As an earlier poster implied, Android using Google Maps, is a very hard combo to beat for accuracy, completeness - especially in less travelled countries.
Portrait sounds good
I like the idea of portrait orientation - it seems like such a basic thing to want to do, but no sat nav I've ever used has it.
Having said that, why would anybody drop 300 notes on a standalone sat nav nowadays? You could buy nearly *two* Android 10.2" tablets for that with GPS built in, and thus you wouldn't be spending 300 on something that only ever gets use while you're in the car.
And how is 'û' pronounced?

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