I have a Toyota Highlander Hybrid 2008. It has everything except A2DP bluetooth streaming, and I want bluetooth streaming so I don't kill myself while driving and trying to mess with aux cords when I would like to hear Pandora from my iPhone. I bought this device for A2DP use only, my car has built-in bluetooth for phone calls. (No idea how it works for hands-free calling)
My jaw dropped when I got this all hooked up and turned on! Synced with my iPhone 4S just fine and did not interfere whatsoever with the connection to the car's built-in bluetooth hands-free calling. I can make and receive calls using the built-in Toyota bluetooth. The A2DP audio quality sounds crystal clear and amazing! I can get out of the car and walk around the garage while it continues playing strong -- only when I walk into the house does the audio start to break up a little. Because it connects though the Aux jack, it won't display on your car's screen the artist/song name or give you any Previous/Next Song controls. I didn't expect it to do any of that, so no disappointment there! What it does do, it does very well.