I have an OD green gen II with maybe 3 uses (3 full mags fired through it) that has been stored loaded with the dust cover snapped on and I recently noticed a crack in the top rear where the bolt goes through the notch. The empty mag wouldn't drop free when I hit the mag release is how I found it, I check my mags often for things like that. The mag isn't very old either. I realize it's only one mag and could be a fluke. It appears the gen 3's are better.
I quit buying Pmags and only buy Lancer hybrids now (L5AWM), so far so good. The lancer mags have a little extra room internally so when loaded with 30 rounds there's still a little room like you could almost get 31 rounds in them which helps inserting a full mag when the bolts closed.
