Having shot and then run a stage at the Lucas Oil PCC Championship, you might be interested to know that the two platforms with no reliability issues were the Sub2000 and the Russian AKs. Granted, each only had 5 or so of each in the match of over 200 competitors. The top 10 had 6 AR9s (top 3, 7, 9, 10) and 4 MPXs. There were a handful of Berettas and JR Carbines, two MP5s and two CZs. AR9s were dominant (with the MPX a distant 2nd), but with all the lowers, that group can be segmented as well. The QC10 lowers were the most trouble free. Squibs, case separations, detonations in the upper receiver were present, and a LOT of magazine issues. 3D printed couplers on all kinds of mags were responsible for most of the feeding issues in AR9s and MPXs. Taylor Freelance basepads (making 41 and 27 rounds mags) and TTI basepads (making 36 and 23 round mags) ran almost perfectly. On some lowers, there was a need to download the 41s to 39 to get 100% reliability. Robin (Taylor Freelance) is working on +20 pads that should be ready in a few months. The Sub2000s just ran like sewing machines and their shorter length and lightweight seemed to give an advantage in speed. However, no top skill shooters ran one. Most were using a reflex sight like a Vortex Venom or a Burris FastFire and all but one were 9mm Glock mag. One was a .40 Glock mag.