Go with the 45. in any instance where you need to have a one shot kill the 45 is the way to go. one solid shot anywhere in the torso or stomach area will give the bad guy probably a huge change of heart. A 9mm will need repeated hits to anchor someone. You might not have enough time to get away or not get hurt with the 9mm. Id personally go with a revolver. You got 6 shots for sure. Ive got a Springfield XD thumb safety and i thought that it was the best thing out there. Until it jammed with Golden Sabers. Up to this point it had shot everything 110% reliably. it held 13+1 capacity. I have now purchased a Thunder Ranch 22-4 45ACP. i know i have got 6 for sure shots, while the XD i might have 3 before it jams or i might have all 14.

But im not completely bashing the XD. it is a relatively inexpensive gun, i think around $600 or less. Once you find a load that will not jam in it, shoot it. If considering the XD get the one with the thumb safety. There was definitely some thought put into this gun. I love its simple and quick takedown system.