I had the same experience. My new ones run flawlessly and as a bonus they hold 2 extra rounds each. I highly recommend them.FWIW, the modified mags that I got from Robertson sort of worked. They would hand cycle just fine, but all three would hang up on the last round when I actually shot them. Maybe Guns America still had examples of their first attempt at modification? I talked to someone at Robertson, sent the old ones back, and got three new ones within a few days. I used all three of them last weekend and they worked just fine. I had zero malfunctions.