In addition to the factory mags that came with it, I have a TTI +1 mag and two of the +2's. One of the +2's is an early release and the other came with the stronger spring from TTI. I've experienced no issues with any of them and after today have 565 rounds through the gun. I don't have a break out by magazine, but most of those rounds have been with the +2 mags as they fit my hands better.