The Avic D3 is a GREAT unit for the money, but by no means perfect.
Had mine for about a year now, and fully satisfied, BUT there are a few annoying quirks.
No RDS. I have NO idea why they didnt include RDS. Very annoying to get used to listening to the Ipod or Satellite (both of which display artist, song, album, etc) then go to FM for a change of pace, and have NO available info showing for a song.
No Album Artwork displayed when using the Ipod. Another annoyance. I spend a fair amount of time tagging my MP3's to include the album artwork. Displays nicely when I use my Ipod by itself. any reason why Pioneer couldnt at least give us the option of having the Album artwork appear on the display?
Bluetooth blues. It works fairly well, but the contact information is fairly quirky. Incoming calls from known contacts that are listed in my Treo dont display as the contact info on the headunit, just the number with "unknown user" or some such label.
Granted, the list of pros FAR outweighs the cons, but just didnt want anyone to think its perfect by any stretch