Can you really "practice" if you take out everything but the trigger press?
.22LR and 9mm -.45 are definitely not comparable. Not to be a smart-ass, but the XD series offerings are not target pistols, they're work guns designed to give a person a handful of whoop-ass that doesn't require a lot of coddling. If the muzzle-flip and time to get back on target aren't the same, it isn't really practice, it's just cheaper shooting. It's like a pro baseball player using tennis balls for fungo. Apples/oranges, and all that.
"Guns don't kill people. Male Kennedy's kill people."