Bought one, didn't know it would be as good as it was for a training tool. It was the best firearm to demonstrate almost every type of failure a firearm can have. Light strikes, FTT, stove pipes, failure to eject, etc. Needless to say, while trying to break in the gun, my wife had first hand experience with almost every failure. When taking her RPal, she raised her hand to the instructors asking students if they knew what each type of failure was. A great training tool.
As a reliable, working handgun, the ISSC M22 is a failure. I tried every type of 22 ammo I could find, yes all of it, including CCI Stingers. I had problems with them all. Eventually I got tired of the problems, wrote the parent company, ISSC in Austria explaining the issues I'd been having. They agreed to replace the firearm. I returned it to the distributor and waited for the new replacement. A smart individual would have sold the new unfired replacement as quickly as possible and got rid of it. But no, curiosity got the best of me so off to the range I went. Same crap, replacement handgun. It has become a project for me now, as I cannot sell it to anyone in good conscious, knowing the inherent issues with it.
It's too bad really, because it looks nice, is quite simple overall but yet a complete dud. Those who say they have had no problems, I'd be suspect of. There is no perfect fix to these things that I've come across yet. Buyer beware of the ISSC M22.......and because of, I am less likely to buy any ISSC firearm, knowing the issues with the M22 - both my original and the replacement one that suffers from the same problems.
You want a good 22 pistol, look elsewhere.