Hornady 200 grain XTP in 45 ACP is 5 fps faster than 10 mm Auto. With custom ammo the spread is much greater. Any 200 grain .400 caliber is enough at 1050 fps. Combat accuracy won't make you send group photos to your friends but 6 inches at 50 yards kills lots of game. I like the feel of SF gripframe compared to standard G20. I also like 1911 style grip but 10mm Auto is a bit much when the grip safety digs into my palm.