I used PMAGS last time I was in Afghanistan, as did most of the guys who knew much about guns (and didn't mind spending money for reliability, knowing that if SHTF you want the best chances). I also noticed a lot of the American units were switching over to PMAGS themselves, I think they were purchased through unit funds though and weren't officially adopted by DOD. But I have no experiences with the pinned PMAGS, although as others have said the newer ones that are properly pinned are excellent. Also if the non windowed ones are cheaper then go with those, windowed PMAGS only start showing rounds at 5 so kind of useless here. But may as well get one or two for the cool factor.