I've looked at whether to change from a 660 to a 350 and it's a close run thing! It's down to personal preference really but for what it's worth - my penny's worth:
The 660 drives me nuts when I'm loading maps or generally have it plugged into my PC because you have to take the back cover off to get at the USB socket. You can't check anything you've done until you've unplugged it, put the cover back on, and booted it up again. The 550 and the 350 with an external USB socket seem very appealling!
In a day and age when every phone has an MP3 player that will either link by cable or bluetooth, do you really need a satnav with one that's also going to need updating every time you change your music collection (which in my case is every week!

)?
Same point goes for connecting a phone really. If you want to use a phone on the move it's easy enough to bluetooth it to your Autocom or your bluetooth headset - which is more than can be said about connecting your phone to a 660 if comments elsewhere on this forum are anything to go by

. Seems to be one of the most common problems people have.
In a day and age when everything demands more and more memory, (and again the lack of it on the 660 is commented on regularly) doesn't it make sense to go with the latest technology and the most memory?

I do acknowledge you can top the 660 with a micro SD card though.
If I hadn't got a 660 already I'd definitely go for the 350.
