re: PX4 Storm vs. M&P

Know some military guys that find some berettas jam a bit more than they'd like but I always considered S&W to be a little too proud of their name. I'd go with the M&P. As far as caliber, I'd go with what you're more comfortable shooting. Both have sufficient power and expansion. Capacity shouldn't be an issue. If you can't hit it with 15 rounds, 18 isn't going to make much difference. Then again, I'm a wheel gun fan.