shoot before you buy if possible.
S&W 642 is the benchmark, however, with .38+p rounds the recoil is stout to say the least and many find it quite awful which makes shooting it very difficult.
a 640 (the full stainless, ie, heavier version of the 642) is quite a bit better in the recoil department. The more weight, the less you feel the recoil. However, an all stainless snubbie is typically two heavy for comfortable pocket carry. So, for in pocket carry, the 642 is king, for belt carry go all stainless and then you HAVE to consider a Ruger SP101. It's heavier and a pleasure to shoot with .38's and actually manageable with .357 rounds. It's cheaper than the S&W and doesn't have an internal lock like the S&Ws.
It would be great to have several, the 642 for pocket carry, an all stainless S&W or Ruger SP101 for Belt carry.
The recoil on a J frame, even with just plain .38's is stiff and many find it almost too much so it's best to try one if you can.
If you really want to soak up the recoil, consider a Ruger SP101 w/3" barrel. makes shooting .38 +p's enjoyable.
God Bless