I've got TomTom Navigator (version 4 i think) and cant recommend it highly enough. Quite simply, i'd be lost without it now!
The latest version lets you put in full postcodes, mine would only let you put in something like S70 5 and then you have to choose the street name you want.
The only problem i have found is that at any one time during the journey, i have absolutely no idea where i am! I know where I'm going, how long it will take to get there etc, but not where i am at present, its like being on auto pilot. 8l1nd
I'd like to try the bluetooth version to see how it compares, mine is wired which looks a bit untidy but it does keep the handheld on charge whilst in the car, so thats good.
It is dead easy to move between cars too, I cant understand why anyone would pay ?2k+ for an optional extra when these little beauties only cost a fraction of that. c7u8
Got mine off the net somewhere, sorry i cant remember where but if you use one of the comparison engines you'll find plenty of places that do them.
Hope that helps!
Cian