I own two of the wireless chargers and am extremely pleased with them. Super convenient (and cool!) and not noticeably slower or faster than any other charging method. So far I've not let my G2 get below 70%, so I don't know how long a full recharge would take, but from 80% full I think it's taken about an hour.
EDIT: After making the above post, I had a chance to time a charge; in the process I discovered I understated my charging times. Taking the phone's battery from 73% to 100% took right at an hour and forty-five minutes. Sorry for the error.