If you want to do pocket carry I'd say get something lighter than the SP101.
If you don't want pocket carry, I'm with C.R. Sam. Get a 2 1/2" or 3" K-frame. It isn't much heavier or bigger when it comes to concealement or carry but the extra size and weight does help a ton when it comes to control and shooting comfort.
My Taurus 605 (2" small frame .357) is a bear to shoot with magnum rounds. Heck, even with +Ps you really do feel it and you wouldn't want to shoot more than a box. You will even feel .38s and would probably go no more than two boxes. With this gun you have 5 shots.
My S&W 65LS (3" K-frame .357) is comfortable to shoot with most .357 loadings (though I'd stay away from hunting rounds if I didn't have to use them). Shooting the stouter .357s will be noticed but medium strength and milder .357s can be shot for an extended period with relative comfort. Shooting .38+Ps you could probably go all day. You barely notice the recoil when shooting regular .38s. With this gun you get 6 shots.
Both guns are a bit heavy for pocket carry (the Taurus is just small enough to fit but it is very heavy in a pocket). Both conceal easily in an IWB or belt hoster. The K-frame is heavier but with a good belt it wouldn't be a problem.
Especially if you think you will shoot many magnum rounds the K-frame snub is the way to go. If you really want (or need) the smaller snub you may want to consider a .38 instead of a .357 (the .38+P is a very effective defensive round with much faster follow up shots than the .357, and there are effective .38 rounds which allow even faster follow up than the +P). If you think you'll want to use pocket carry consider one of the lightweight aluminum .38s, that way you can best take advantage of the one advantage of the J-frame (and equivelents) over the K-frame- light weight and smaller size for pocket carry (the heavier .357 small snubs are really too heavy for most people to pocket carry).