Well, let me inform you of the absolute truth here.
The.45 APC round is the better of the two.
Why?
Because "I" like it, because "I" said so, and because Elvis died and made me king of the world right after he realized that the world revolves around me.
So to all who disagree, do not confuse me with the facts, I will agree to disagree with you because you have a right to be wrong.
OK...... now that I am awake..... ( I was having the coolest dream!!!)
I will put in my .02$ worth.
I do like the .45ACP best personally.
I've owned .38 .357 .357mag .357sig .40 .45ACP .22 .22mag and .32 handguns and I like the .45 the best for personal defense.
I liked the .357sig and .357magnum for their penetration in certain circumstances. But statistically, as a civilian, I have a much lower chance of needing to shoot through car doors, windshields, walls etc than I do of simply needing to shoot a potentially deadly criminal with nothing more than a thick jacket on.
The last thing I want is for that round to over penetrate and go through the target to strike an innocent person behind them or through a wall with the same result.
The .357magnum was designed as a hunting round if I am not mistaken, and the .357sig has almost identical velocities in many rounds.
With the standard .357 you have fewer over penetration issues than with the mag or sig, but a much smaller projectile than a .45
If I am forced to discharge a weapon at an attacker, I want the largest, safest, and most reliable round I can effectively shoot.
Effectively shoot being the most important of the four in my opinion.
If one can only effectively shoot a .22short then they are better off hitting the target with a .22short than they are missing the target with a .50 hand cannon.
However, modern technology mixed with high quality products has made large calibre handguns quite manageable in my opinion.
My wife is 5ft 1" with very small hands.
She carries a H&K USP .40 and shoots it VERY well.
The gun is completely stock with no mods and she can shoot 200 rounds through it one handed with little to no wrist fatigue, and stay on target to the last shot.
That's far more than enough for any "on the street" self defense situation.
I carry a .45 ACP.
My last carry gun was a Glock 33 in .357sig. In test fires it went through a car door, glass (window rolled down) and a leather jacket wrapped around a pumpkin, and on into the door panel on the passenger side. When fired at the kevlar insert for a LE grade vest, two rounds stuck through the other side and the third went all the way through to put a dent in a metal canister behind it.
The .45 went through the car door, the jacket and partially into the pumpkin. It also only wet 1/2 of the way through the Kevlar.
When both rounds were fired directly into a bare pumpkin the .357sig left an exit hole about the same size as the entry hole. and through a 1/2 inch sheet of plywood behind it.
The .45 blew out half the back of the pumpkin and lay on the table after striking the plywood with just enough force to tell where it hit.
Now, since I won't be firing at cops wearing Kevlar, and chances are I will never have the need to shoot through cars to hit an attacker, I personally believe that the over penetration issue is to much risk.
Especially when the .45 seems to do the job nicely and is a proven man stopper.
(Yes, I know that my unscientific tests and the use of pumpkins certainly do not even pretend to be as reliable as ballistic gelatin or actual shooting statistical data, but it gave me a reference point to begin with for my own satisfaction of what to carry, and rely on. Besides, I'm not Massad Ayoob. I'm just "me-BN-me" relating my personal unscientific, backwoods, caveman grade tests.)