I'm new to the forum. So it is with some trepidation I offer an opinion on such a subject, but here goes:
For a first single action, I'd have to agree with Ruger being the best first choice primarily because they have adjustable sights. The Beretta Stampede is a very well finished gun, I have one in .45 Colt - chamber throats, forcing cone, alignment, and lockup (like a bank vault) are perfect, but it doesn't have adjustable sights. I also have a .45 Colt Ruger that I wouldn't part with. It's a great gun.
I have the 50th .357 Blackhawk and like it a lot. Bought it used as a shooter (no box, no papers, just the barely used gun - no cylinder ring then, it has one now) - it is a sweet shooting handgun - it is sad to think of so many of those fine guns sitting in safes unused. The smaller frame is nice if your hands aren't too big. The gun is just plain "handy".
That said, the 6-1/2" barrel blued .357 magnum Ruger Blackhawk with adjustable sights is a heck of a good first .357 magnum single action. It carries nicely in the woods, is comfortable to shoot with full magnum loads (if you grip it right), more accurate than most shooters, it usually has good fit and finish, and it is reasonably priced.
Unless you have a strong reason to get a Vaquero I'd recommend one of the models with adjustable sights.
The stainless ones are OK but personally I prefer the blued guns because the barrels and chambers are usually considerably better finished and I've never had a gun rust even growing up in Michigan. The stainless ones are mostly acceptable, but after a couple of bad experiences I won't buy one with out running at least a dry patch through the bore and looking at it and the chambers, with a good bore light.
You might see if they have one to rent at one of the local ranges. Trying one is less expensive than buying one and finding out you don't like it after all.
If you haven't fired one before, there are a couple of things that might make shooting it more pleasant. The generic single action revolver (Colt SAA) was designed to be fired one handed, probably by a guy on horseback. If one holds it in a conventional two handed grip the second knuckle of the strong hand will be tucked in behind the trigger guard and it will get whacked hard - it hurts - when shooting magnum ammo. But there is a solution for this. Hold the gun with the shooting hand as if you were going to shoot it one handed. Let it hang down at your side so the barrel is in line with the forearm. Then bring it up and wrap your support hand around it with out shifting your grip. This usually moves the second knuckle out from behind the trigger guard, at least it does for my wife and I, so shooting it is pain free even with magnum ammo.
Fitch
