Garmin i3
Just bought one of the Garmin i3's for my wife. As previous posters have said, it's not waterproof and there is no external speaker jack, so it's not much use for the bike. Apart from that, the screen is reasonably small, so again, bike use (say in a tank bag or something) would be limited.
For in the car though, great!
Full UK postcode lookup. You can load in the speed camera positions and recieve an audible warning when you approach their positions. 2D or 3D mapping.
It seems to have a really simple user interface with a thumb wheel for entering address information. Much simpler for someone unfamiliar with GPS systems to get to grips with.
Runs off 2xAA batteries or 12v supply with adapter lead (supplied).
The only thing it doesn't allow you to do as far as I can tell, is download routes created in Mapsource.
All in all, a top piece of kit, especially for £199
Cheers
Pete