I have the 910 and bought it for £499 from dixons and its gone down so much.
Personally, I would buy a tom tom one as they are so compact and would get a little ipod to play music through there, i would not use the tom tom it has about 100 functions you will never use.
The good thing about the 910 is the euro and USA maps, plus the little pouch you get for it, all the extras including the external aerial and the remote
Worthwhile toy but I might have gone for the one now, (dont know if it has bluetooh, i like that functionality.