For a general purpose revolver, get the GP-100 with four-inch barrel. Keep looking for the thee-inch SP-101 for a smaller concealed carry gun.
I think the shorter SP is too heavy for a good snub and would opt for an older S&W M-60, without The Lock.
A 3" SP is pretty heavy for size, but when you fire Plus P .38's or full .357 loads in it, the weight helps a lot with recoil. Mine is quite accurate and is considerably easier to shoot well than a snub.
The larger 3" GP is probably going to be too bulky and heavy for most concealed carry, although it can be done with the right clothing and holster.
Good luck in finding a SP-101 with three-inch barrel. They're well thought of on both Ruger boards, and members look for them. I don't think Ruger makes enough to meet demands.
Frankly, if I could only own one handgun, the 3" SP would probably serve pretty well. With full .357 ammo it'll even protect you from most wild animas and can take small game handily, or shoot snakes, etc., as well as being a basic defense gun. It's the smallest such item I'd consider. The only drawback is the five-shot capacity.
I think you'd be well served if you have a 3" SP-101 and a four-inch GP-100. Ruger triggers wear-in well, and both of mine are quite smooth. Don't believe all the nonsense here about bad Ruger triggers. It is true that S&W triggers are usually lighter, with a shorter travel in SA firing.