This always surprises me. For terminal results, if it's a .38 spl, then a .357 mag is better. If it's a .44 spl then a .44 mag is better, but the death ray .45ACP standard velocity is as good as it gets.I recently saw an article somewhere that concluded the +P version of the .45 was not much of an improvement. In shooting both, I would go with the standard loading to get back on target quicker.
They are pistol rounds. I think any velocity increase is a good thing, if one can handle the recoil.