For a while I ran a Hogue Monogrip on my 340MP just because recoil was so unpleasant. Problem is the Monogrip is huge, and makes pocket carry about impossible.

I then went to the Pachmayr Compac Pro (pictured) and liked them a whole lot. Harder rubber than the Hogues, less sticky in the pocket, and still plenty to hang onto at the range.

I really like the look of the G10 grips by VZ and the wood from Spegel. My next J-frame will wear one of these two for sure.