Hello, I have had the tomtom go for a few years know. It's just the basic 300 with the speed camera on.
I have never looked in an A-Z since and wonder how I got on without it.
Very easy to use - takes a few days to get used to directions/etc and you need to look/read on screen map aswell. You can put speed camera on and it tells you the speed of camera aswell.
You can get them with built in hard drives, mp3 players, hand free bluetooth, european maps thats the more expensive ones.
Never used any others so couldn't comment on them, but I am pleased with mine.
Hope this helps.
Regards
Paul