Been snooping around a bit on this unit, I've seen a few things pop up. The F30 forum has a large thread going on their unit here:
http://f30.bimmerpost.com/forums/sho....php?t=1374452
I've seen a bit on the E90 side, one forum here:
http://www.e90post.com/forums/showthread.php?t=1424151 and there is an install overview on another forum you can find easily through googling "avin bmw e90" (bimmerpost isn't letting me link it)
There is a competitor (4x4shopcanada) that seems devoted to trashing AVIN, but no information is available on their units from other people. They also seem to use a pretty much identical unit, but with a worse processor. You can also go through the manufacturer in the original post, but it seems like AVIN offers much better support and constant updates (which seem to be necessary).
It does seem like a few problems have popped up on the AVIN systems. They originally had some overheating issues, which was resolved with an updated unit with bigger heat sink. To fit in into the E9x, you have to trim the unit a bit, but it’s not visible. It connects via AUX to the stock system. On CCC, supposedly the unit connects in the back, but CIC you have to connect it to the AUX input in the center console (I believe). Audio quality seems to be iffy through Bluetooth, and okay (but still worse than factory) through the AUX connection.
Looks like it offers the most benefit to people with CCC. May try it out toward the end of this year.