You don't mention your experience level in handgun shooting, and I think that is (or should be) a major point in the selection process.
Originally Posted by nuc
Firing very powerful handguns quickly and accurately is not something that happens overnight. As DanP mentioned above, "2. You do have to hit something for all that energy to be effective." Put another way, a miss gets you nothing, and a less-than-vital-zone hit might get you a more riled-up critter than you started with; not a good thing. If you are already a very experienced handgunner, then the .44/.45 mags might be reasonable choices; if you're not experienced with powerful handguns, then I'd say the .357 wins by default. Load it with the most penetrative ammo you can find, practice WITH THAT AMMO at least some of the time, and give some thought to the circumstances you might find yourself in if you need the weapon (one-hand firing, access to the holstered weapon with either hand if one hand is otherwise engaged, etc.) and practice with these needs in mind.
I currently own a full-size (7.5") Redhawk .44 Mag and a 3" GP-100 .357; in the past, I've owned or fired 4" and 6" GP-100s, and 4" .45 Colt and 5.5" .44 Mag Redhawks. You really have to want to carry a full-size magnum revolver quite badly to put up with the weight and bulk; a 3" or 4" .357 is MUCH easier to deal with size- and weight-wise, as well as being easier to learn to shoot well with serious loads.
A photo of my Ruger revolvers, from a few years ago; the center 4" GP-100 is gone now, but I still have the other two.
"Placement is power" -- seen in an article by Stephen A. Camp
(RIP, Mr. Camp; you will be remembered, and missed)