I prefer the 9mm. In fact 124 grain +P are what I carry in my Sig. The 9mm has been putting down guys for well over 100 years.
I like the 9mm, too. With the right ammo, it does the job. The main reason I like it is I just seem to shoot it better than 45, not that I'm bad with a 45. And having 15 shots in the magazine is nice, too. But if I was in the Army and doing CQB in some urban hell hole, forced to use ball ammo, I'd choose the 1911 or some other 45.