Well I went to Audi yesterday to try out the new rSAP phone adapter for the car kit in my A4. Looks like a really great bit of kit. However it didn't work with my Sony Ericsson P1i or my k700i the p1i wouldn't sync the phone book (worked on calls) and the K700i kept crashing when sync was running.
I'm getting my new phone next month, so I'll go back and try that one, but I was a little disappointed. but I think thats cos of my kit rather than the rSAP to be honest.