November, Trek OCLV, Bianchi Castro Valley commuter
For listening to gps directions, I think any bt over-the-ear unit with sufficient volume will work. I use a Plantronics Voyager Pro headset with a blue-tooth-equipped amateur ("ham") radio; it works quite well once I added a foam mike cover to block wind noise.
I think you should consider wired headsets as well. GPS + Bluetooth drains my battery way too quickly. I use a Jabra Wave with Endomondo as an audio cycloputer (I don't like the numbers staring me in the face). It sucks getting wired up, but once I am on the road I don't notice the wire.