The system requires a changer or changer prep because the ipod adapter hooks into CD 7-12 and the in-dash or other changer uses CD 1-6. At one time there was a conflict between the satellite radio connection and the ipod adapter connection (you could only have one or the other), but I think that has been solved by a harness change.
However, all that being said, the OEM adapter is disappointing. When connected, the controls on the ipod are disabled and you can only use the steering wheel or radio controls to operate the ipod. In addtion, the mode of operation is that it assigns your first 5 playlists (in alphanumeric order) to CD 7 - 11 and CD 12 is all songs (alphabetical by song title). Now this may not sound too bad until you realize that no title or artist information is sent from the ipod to the radio display, so all you see is a track number. I haven't quite figured out the best way to organize my playlists to make this workable.
The best workaround I've found so far is that you can unplug your ipod, go to a specific album, press play and then reconnect the ipod. It will then play the album in its entirety.
On the plus side, i like that it charges your ipod while it is docked. Mine was a factory installation so there is a little pocket in the glovebox where a hard dock is installed. It is not just a loose cable like in the picture. It's secure and out of the way of prying eyes when the car is parked. Sound quality is good as well. If it wasn't for the crappy user integration, it would be great.
There are many other aftermarket versions that have different operating characteristics. None send text information to the display last I checked, but some allow you to operate the ipod from it's own controls while connected.
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