I have a 99 540i and a retrofit BMW Bluetooth Kit. Install was very simple and I am very happy with the system. I've only tried two types of phone on this system. The V600s that I have tried have all worked perfectly. They sync the phonebook and have a very good connection. My main phone is a Verizon V710 and this is less then perfect. Overall I can get them to connect (no phonebook transfer), but every now and then it'll connect / disconnect in a never-ending cycle. If I turn off the phone and turn it back on things are better. Overall, I think its worth it.