In my opinion both are excellent. I don't know what type of areas you are able to shoot/practice etc.... but here is something a bit off topic that one might consider also. If you only practice at a range....no worries, but if you are a person (redneck like me) who dwells in rural areas and might have permission/opportunites to stop off at the neighbors pastures, gravel pits, creek banks, etc... to shoot a few rounds......the 45 at sub-sonic speeds is MUCH quieter. My family knows EXACTLY which gun I am shooting in the pasture when I have my 3" 357. They don't mind, and no harm is done, but my point is when/if targets or practice shots of opportunity arise, and you might not have time for earmuffs/plugs or you might be within a reasonable distance from neighbors...so the noise might be something to factor. I find myself not shooting at things while out in the woods with my 357 that I'd probably shoot at with a 45acp. Everyone would still here the shot with either, but it is like..."oh, someone is target shooting over yonder" compared to "holy **** that person must be close!".
Having said all of that, I don't have a 45 anymore and I carry a 3" Ruger SP101 that I love. I can shoot 38's when I want to be quieter,,,,,but I never do. I just make lots of noise and keep earplugs in my pocket