I choose both, but its not allowed. I own mostly 1911s in the proper caliber,lol, but also have a pair of 40's in tupperware as well. Either caliber is good, though the recoil is not as sharp when shooting the 45 vs the 40. You get more rounds in a mag with a 40, but other then target shooting, IMO more then 8 rounds is moot, except when arguing for the right to carry more then 10. Make sense?lol.