I have the Q2 teamset. It works great with 2 riders, but when trying to connect a third it seems to have some problems.
I got a great deal on craigslist $160 shipped for the pair, brand new!!!
Definitely nice to have on long rides with a friend, or when the gf wants to go along. Last friday I used it almost continuously as an intercom for 8 hours, and never got a low battery indication. Will see how much longer the charge lasts. During that ride there was one instance where the units wouldn't connect with bluetooth. My friend was still able to call me through the connected phones. I turned mine off, and back on, and all was well.
I routinely ride with the same 2 guys and we all have Q2s. It would be nice to have the ability to all talk at once like the G4 offers, and if I read correctly it seems that with one G4 you can talk 3 people in full duplex, so I might be tempted to put up the money to give that a try.