The logical arguments against are pretty well laid out already.
I carry a 3.75" birdshead Vaquero in .45 Colt pretty much everywhere. I built an appendiceal IWB here:
and am about to order a Mernickle holster that looks very very much like the one Bob Wright has pictured a few posts up from here.
In favor of the SAA and similar, to me is the power to weight to size ratio.
If you want to carry .45 Colt .44Special or similar, the reasonable choices are derringer, N frame size DAs (and similar) and the Charter Arms bulldog.
I practice with my sidearm a lot. For someone like my mom who goes to the range maybe twice a year the bulldog might be a good choice.
Likewise I am a good enough and confident enough shot that putting up with the bulk of a Judge variant to stuff it full of .45 Colt is a waste of cylinder length.
I own a Redhawk in .45Colt, I open carry it in the field, practice with it regular year around and will likely even tote it around as my primary carry sidearm in the weeks leading up to (and during) hunting season. I'll also shoot some steel target matches with it this summer.
But it is too dang heavy (for me) for year round conceal carry, and frankly to bulky for summertime concealed carry even in Alaska.
I used to carry an Airweight SW .38+P snubbie. An Aluminum one, not the heavier plain steel, but not the high dollar unobtanium either. I was perfectly happy with it until I starting blowing stuff up at the range with plain Jane .45Colt loads. Soda cans, tomatoes, cantalopues, 2x4s, that kinda stuff.
So here in the one hand I got a definitive one shot man stopper (if I do my part) that is too heavy and too big for year round conceal carry, and in the other hand I have a light weight little thing that will not print if I ever buy an Armani suit that works pretty well in the hands of full time professionals who train heavily.
Hmm. I shoot a fair muchness for being a civilian with a hobby, but I am not a pro by any stretch.
So how can I get the power without the size?
Derringer, the local to me one I measured was a Bond Arms with a .45LC/.410 barrel on it. Apparently they make a barrel that is .45LC only, haven't seen one in person. The rifling on the .45/.410 barrel is about 3/4" long from the end of the .410 chamber to the muzzle. I hear they kick like mules, never shot one, and compared to the Jframe .38 snubbie referenced above, every meaningful difference was +/- 0.1 to +/- 0.2 inches. I had no idea the diameter of a 5 shot .38 cylinder was within 0.2 inches of the thickness of a .45LC derringer, but it is.
All this, for a two shot gun that weighed more than the snubbie, only carries two shots, has shorter rifling, and apparently the second barrel on these often needs its own sights. I found a couple web pages about how to install a second set of sights on the side of a derringer so you can hold it gangsta style but sight it like a responsible adult when you need to fire the lower barrel.
Seemed like a fork in a bad road.
Next size up is the short barreled SAA and clones. I found mine, and bought a .22 SA revolver for training.
My Vaquero groups real nice out to 25 yards, chambers 6 cartridges that start with a four and is light enough to carry day in and day out.
With the .22 I have thrown about 6% of the lead Elmer said I would need to be a competent hip shooter. Mr. Keith said about 10k rounds in his book _Six Guns_ , I am to about 600 rounds in and I think he called it about right.
Another quote I think from Massad Ayoob the OP might wish to consider:
Originally Posted by unknown gun writer
No one who survives a gun fight goes out to buy a smaller gun the next morning.
I know I am in a small demographic, but it is a thoughtful group that practices a lot.