We've got a Dension in the Skoda, a dealer-accessory-fit. It's OK, but the head unit has limited display capability so although you can control tracks (having gone through the lottery of key-presses to set the control mode

) there is no track or playlist info available etc.
It does the job for us for now, and it was free as it happens (part of my wheeling and dealing on the car purchase itself). However I think a head unit upgrade would be needed to get the best out of it.
I'm interested in a new head unit and ipod controller for the elise but only if I can get a head unit with the GALA-type speed-sensitive volume adjustment. Don't see many around?
Also, back on-topic, Pioneer do a wide range of ipod-controller head units last time I checked.