Well the BB Music Gateway arrived yesterday. I have to say I am pretty happy with it. Sound quality is pretty good - not CD quality but neither are most of the rips I am playing.
Setup was a snap too! My Lumia 620 has NFC so I just had to tap the phone to the gateway to pair. Setup literally took less than 10 seconds.
Now I can play all of my music on my car which is what I wanted.