I have one of these, but I do not have a large number of rounds through it. The barrel fit and the slide to frame fit are equal to or better than most of the Factory STI guns I have shot. The frame on these is not identical to a para, the dust cover is substantially heavier and the grip is cut short to accommodate the mag well. Internally, these appear to be Para style guns.
Mine runs fine on STI 140mm magazines, as well as the magazine it shipped with, which is made by ACT magazine. Megcar P16 magazines are shorter with very different feed lips, and, due to the magwell, require different basepads to seat at all. I chopped up my feed lips and basepads to make them work, but in the future I am just going to order the ACT mags or STIs.
For a holster, I am running a Safariland 5197 for a Short, Wide Dust Cover STI 2011, which I had to stretch slightly to get a smooth release.
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