Bought it out of convenience for $74 (no shipping though) when I got the 7100. Can be had for about $48 on ebay but $13 or so for shipping.
What I like:
Has worked flawlessly with the 7100g so far. If you put it in trusted mode it connects automatically.
Small and comfortable.
Works great in quiet environments - house, hotel room, car with windows closed and VOL is plenty for me in those situations.
Some have said it's not useable in louder areas, but I am not often in that situation.
What I don't like:
Charger is not mini-usb which would avoid yet another transformer. At least it is small.
Bottom line - works so well not worth the hassle of returning it. Might consider a newer one sometime down the line especially if there is an upgrade to 1.2 and BB supports more functions.