Wow that sounds really bad. I guess that means they have lemons then? Just saying because from what I've seen, not all do that including mine. But now that I see it's more then one person, sounds like they have lemons. That is a bad if safety malfunctions.
I'm not sure about that racking slide with safety on, but it sounds like something I wont do.
I never experienced that in my 2+ months with my baby when I put safety on.
My old KWA M9(metal slide version) had a trigger spring problem. It broke after a couple hundred shots. I just got it replaced with a real M9 trigger spring(got it free at AEX). Then I had it for another year through over a thousand shots with no problems. Then I sold it to my best friend(still no problems but I think recoil spring needs to be changed now).
I now own the new KWA M9 PTP. Goen through a couple thousand so far and no problem. I love her to death. Never felt or used a stock pistol like her. Other then accuracy for stock, it is perfect. Just don't expect to use it medium range