For me the choice of 9mm really boils down to capacity and how cheap it is to shoot. Shooting is a perishable skill. I like to put at least 500 rounds down range a month at an absolute minimum to keep the rust from building up. That's much easier to stomach with 9mm with cost per round. My CZ P09 also holds 21 rounds per mag. I'm over 60 rounds with 3 mags or 40 with 2. Loaded up with hollow points I'm not too worried about "stopping power" because I'm likely going to hit something vital if I keep the shooting sharp.