I have a 9mm core with porting, and after comparing it with my non ported 40cal core, I don't see enough difference between them to justify porting. The porting on the 9mm does look trick however. Small gun I wouldn't bother because they aren't range guns. I have a PM9 and I can't imagine porting it. You just want it to go bang when you need it. Porting comes into play on 357magnum revolvers. There I could justify it because muzzle flip is very pronounced.
