With all my previous radios (aftermarket and OEM), I've used my ipod via usb to play music. The functionality is great, but I hate having to use itunes to update my music.
There are lots of double dins with usb and/or sd card slots. Which companies operate the media storage the same way I described the ipod connection? I'd like have things like artwork, the ability to sort/search by albums, artist, genre, etc. I know the mp3 tags need to be set up correctly, that's not a problem.