If at some point you'd end up with both; wait till funds allow for, at least, a Ruger. I prefer S&W but the Ruger wheel guns are a tremendous value. A used GP 100 would serve you well. Plus, if you decide to sell it, a Ruger will have a much better resale market. If you insist on one of the above, the 4" would be my preference if I only had one. A 2" 357 magnum is a much less user friendly weapon than a 4" or 6" barrel revolver.
I'll look into 'em sometime today. Thanks.
@Jmarriott: I am unable to respond to your PM due to my low post count. Not ignoring you, lol.