Works perfectly. However, there will be short interruptions.

I use it in an Audi A4 2011th
Connected connected to my iPhone and it started already.
Synchronization works well. Playlists are displayed on the screen.
With Spotify Although the title does not appear to be delayed, but that's not bad.

Two minuses, there are.
1. Sometimes the product will not start. But that often happens when you have not plugged on "Media" key.
Solution: Just briefly unplug and reconnect. Works again.
2. It then drop outs. If you are connected in parallel with the hands. Then "hack" it a bit, for 10 seconds, then it goes back.
Added: I think it's great that I can simultaneously use both Bluetooth interface!

In summary:

Super product. Recommended. The best alternative for the extremely expensive Ümrüstung of Audi. If at all something to offer;)