For others that may be interested, I am in the midst of my free trial with this phone, and so far, it works very well with the Bluetooth/Assist module in my '05 X5 4.4i. I have the -114 module in my vehicle.
No addresses transfer (no speed dials, synched contacts, or SIM Contacts), but aside from that, it pairs easily and one can make/receive/transfer calls with no problem. You can use the voice activation in the vehicle to "add names" of those you would like to voice dial.
The only catch is that if you will be transferring calls to/from the car and handset, then do not set the phone to "pair automatically". If you do this, then each time you transfer a call back to the handset, it will automatically transfer back to the vehicle after 5 seconds.
This phone works almost as well as the Sony P910a.....