I just bought this and had it installed at Best Buy. Cost was $200 including installation and install time was about 1.5 hours at the store. The initial pairing to my phone was just a matter of going into the Bluetooth settings and selecting the TranzIt blu. Now it pairs automatically each time I start the car. It also begins playing music from my phone automatically after about a three second delay.
I bought this unit to be able to stream music such as Pandora and to make hands free phone calls. My car has the Bose sound system and therefore fiber optics from the receiver to the speakers. If my research is correct, the only way to achieve the hands-free phone and music streaming was either through this type of unit or a replacement radio with a complete rewire.
Sound quality appears to be acceptable to me, about the same as FM radio. The install technician said he thought I lost a little volume compared to the radio. I need to use it a little more find out if that's going to be a problem. If you haven't already seen it, here's an information page from the I-Simple web site.
TranzIt BLU HF by iSimple