I cant help you about the Jawbone 2 bluetooth, but I have a motorola H710 Universal Bluetooth headset and the quality is way better than my old POS samsung slide phone. I can control the volume on BOTH my headset and the phone volume will also adjust the headset volume.
I did have some connection problems at first with the Tour storing the saved information about the bluetooth, but its taken care of now and connects automatically with I turn on the headset.
I know this wasn't your question, but hopefully it will help a bit. Good luck.