My Briley 38 Super Mags solved the problem I had. I broke both of the factory mags that came with my SA 9mm trying to bend them so they would lock the slide back. One would fail to lock the slide back on the last round about 50% of the time and the other one would never lock the slide.
On a side note I emailed SA about the problem and got a "canned" reply stating that they were sorry that I was displeased with their product and hoped that I would try them again in the future!!!