I just bought the Garmin c550, which was $520 on the internet. Apparently it's come down to $499 today:

http://www.abesofmaine.com/viewproduct~id~gmspc550.htm

I really like it. Since it's bluetooth, I paired my cell phone to it and downloaded the phone contacts. It came with a 6 month subscription to Clearchannel's traffic notifications.

And it was very easy to set up.