I had one of these. In theory it could have been the greatest earbud ever. Unfortunately I had constant issues.
First, you cannot keep it in the traditional diagonal position for an earbud as the microphone rests on your cheek and is thus muffled.
Second, and this is what really pissed me off, the mic eventually stopped working. I would try the voice dial and it would never register my voice. Call after call would come in and I would answer without the caller being able to hear me. Seriously, the only way I could get it to finally work was to throw it at something...i.e., the ground, my dashboard, my windshield, the walls, etc...
I retired it and it has since been lost, possibly in the wash. I currently switch off between an invisio g5 (as small as the jabra with few issues) and a Samsung WEP470. Neither have A2DP and I must admit I miss that, but actual functionality is more important to me.