I use the cw9 's 7 round mag or an 8 round mag in my cm9 at the range at times. When useing the cw9 the 8 round mag runs great in it also. The 8 rounder is allways a back up mag. Heck I have never had a failure of any kind in the several years I have own kahrs. My cw9 did come as a used problem handgun, but for me it has been trouble free for close to a 1000 rounds. Owners and ammo can cause more issue than any thing with small light handguns. But I have not used the extended mag with the funky black plactic wrap on it ether that many have problems with.
Heck if you don't like the cm/pm and don't plan on pocket carry get the cw/p series. Full grip there for all but the largest hands and very easy to shoot and control.