I heard good things early on. I bought a few to try but gave them to my buddy that just got into shooting. He said they make his gun jamb. He actually blamed a broken trigger pivot pin on it. I've never heard of a round failing to chamber breaking a pin. Actually haven't heard of many pins breaking at all. Back to original point. I have like of ten of these should I trade them away while they are new. I have no other polymer mags except the Lancer L5, all the rest are GI type. Are the feed lips reinforced? should I cut one open to see whats inside? Anyone use them.