I chose this headunit:
Sony MEX-BT5700U Radio / CD / MP3 player / digital player
PROS:
It covers pretty much everything bluetooth wise, A2DP, AVRCP, Handsfree, phonebook transfer...
-Within 10 seconds of starting my car, both handsfree and A2dp are connected, once in awhile, (maybe once a month) it will connect only handsfree, but all I have to do is push the play button on the strereo and it usually reconnects A2DP almost instantly.
-Shows an onscreen display of your phones battery life and cell signal strength.
-Having hard buttons on the headunit to start/stop/fwd/reverse music is excellent*
-When a call comes in, you hit one button to answer, once the call is done, it goes back to whatever you were listening to before.
-You can transfer the phonebook from your phone to the headunit for permanent storage
-Stereo comes with an internal and an external mic, both of which are VERY GOOD, I've had NO ISSUES with people being able to hear me when placing calls through the stereo
-With this setup, I don't even have to take my droid out of my pocket if I don't want to, just get in the car, hit play, and I'm good to go
CONS:
-I do wish that my stereo would display track information on its display, I believe it is capable of it, but I don't think the droid outputs track info via bluetooth
-If you wish to dial from the headunit, you have to change the source from BT Audio to BT Phone, which means that you won't be hearing your music (Which is the desired effect, you're placing a call, you don't want to hear your music) the problem comes in after the call is disconnected, the stereo doesn't automatically switch back to Bt Audio. (I believe if you start the call from the phone itself it autoswitches)
-The backlight behind the volume knob is VERY bright, and there is absolutely no way to adjust it, even if you have the dimmer wire connected. I was getting blinded by this at night so I covered the offending led with blue fingernail polish and it solved the problem (and still looked good)
*Depending on which app you use to listen to media on your droid. After talking with some developers, I've learned that android has an issue of sorts with bluetooth controls, it doesn't always know which app to send the play/pause etc commands to. So alot of times you will hit play and you will have 2 media players respond to it. I use doggcatcher for podcasts, and they have circumvented this issue by having an option in the menu to "Bind to headset controls" which works great until I need to use another media player... then I have to go into the settings in doggcatcher to "unbind" the controls so other players will respond to the commands.