I stand corrected on the pressure thing, but a .45ACP+P is still WAY more performance than anything you can eek out of a .40 due to the .40 operating, by design, at max. The .40 is not going to equal or replace the .45. It is just a fine little thing in the middle for those who don't need or or think they can handle the .45. Makes them feel warmer and fuzzier than toting a 9mm.