I can only speak to cm40 but maybe somewhat applicable.
Mine had to go back to factory due to FTF/E issues from my first mag, even after 150 rds, still needed to go back. Once it came back. No dysfunctional issues.
I wish now I would have gotten cm9. The 40 is just too snappy, waaay more than my Glock 27 40 cal, imo. I can fire the g27 more accurately with one hand than I can with two hands on cm40, for comparison. Trigger is really funky and long for me, but smooth. If I were to shoot only that, I'd probably get pretty accurate, but it's so much different from all other semi-auto's that I rarely shoot it as to not mess me up with the other stuff. To me, the trigger is more like a revolver than semi-auto.
The positive is that it probably provides the most power and economic value for the smallest, lightest, narrowest package out though! Unfortunately, for me, since I can't hit anything with it, it's not for me. Hope that helps some.