Hi...
I hope I never have to choose only one.
There are at least a half-dozen .45Colt revolvers around here along with a S&W M1917 in .45ACP( I shoot .45AutoRim in it exclusively) and I have no interest in getting rid of any of them.
No idea which is my favorite...that usually depends on which one I am shooting at the time, but I would be hard-pressed to give up my S&W M25.