Nothing beats the Kahr 9mm for pocket carry
I'm still inclined to agree with this.
I have a PF9. It works, but it is not even close to the class of the PM9. The Kahr is more accurate and easier to shoot well - but I have to admit that I am very much in tune with the Kahr trigger. The striker fired slide is less prone to gathering pocket lint.
I've checked into the Sig 938. Too small a gun for me to reliably manipulate the safety at speed. Not that I'd want a SA auto in my pocket anyway. I haven't tried the Ruger pocket pistol, but I haven't heard anything bad about it.
