There is something to be considered regarding using grips which fit your hands properly. People have hands of all sizes, and a gun which has grips which fit large hands well may not perform very well for a small-handed shooter, or vice versa. It's a little more complicated than that, but I'll leave a more detailed discussion for another time. Sort of similar to shooting a shotgun. A top trap shooter or skeet shooter will have his shotgun stock dimensioned (drop, length of pull, cast-on or cast-off, etc.) to fit his body properly and provide a consistent hold and target picture. Stocks provided by the factory are made to fit the "average" shooter reasonably well, not so much larger or smaller shooters.

Regarding shooting a handgun from a bench, I always shoot over sandbags. I use a two-handed hold for maximum steadiness and rest only my wrists on the sandbags, not any part of the handgun itself. With some practice, one can shoot about the same size groups as can be fired from a Ransom Rest. I have used those also. Sandbags are far cheaper.