I've heard several different takes on matching, and also that yes, they are matched at 20 amps, and yes printed lables. I suppose they may have a "tolerance range" to match the labels into. Not standard practice as posted but bottom line, for $36.99 I payed for 6 cells (about same cost as unmatched I compared to), These cells IMO hold up quite well to the competition $ for $. Matched IB's may have a slight edge, but I doubt it would be much more then that. I personally like the stability of GP's (always reliable for me) vs the IB horror stories I've been reading lately.
Throw out the matching and use the $ for $ and speed vs speed if you need. Also, I didn't note but GP's lasted longer too. I got 4.18 miles (ran till dead) on the GP's and 3.93 miles in the IB's. (bottom reading on GPS is distance traveled with steady throttle after 4 speed runs per pack)