The wife carries the 40c, I carry the full frame 40... we both have blackhawk serpas for sr9, and it works great... had to loosen the level one (friction) retention a bit on both holsters, but they carry well, and are easy to draw quickly... neither wife nor I have had the "booger finger hits the trigger" problem that some have with the serpas, though I'm not sure if this is due to the exact layout or the sr/serpa system or just good draw discipline. Trigger was rough and gravelly on the first couple of boxes of ammo, but after a few rounds and a good cleaning, these pieces have a wonderful trigger, imho. As for misfeeds, etc, the only time we've ever had the guns NOT go "boom" is when we're mixing snap-caps into the loadouts to PRACTICE misfires... overall, after about 1500 rounds through each weapon, my wife and I are both impressed with this weapon.