To me, it's a matter of picking the gun and the cartriage. Odviously, you have to be shooting the cartriage in something.
Then it comes down to what you use a handgun for.
With all of that in mind, I do more types of shooting, hunting and carrying concealed with the .45 ACP in a 1911 or a SIG 220 than anything else.
If open carry in the field were what I did the most of, it would be the .44 Magnum in a Smith 29.
I've carried, shot targets and hunted with a wide variety of handgun cartriages. The 5.7 FN, the .256 Winchester Magnum, some 9mm's, the .38 Special, the .357 Magnum, the 10mm, the 41 Magnum, the .44 Magnum and the .45 ACP. Except for the single shot .256, just about any of them will work for most handgun chores. But the .45 ACP, in a quality 1911 is the one I enjoy the most. E