The standard and price/value winners are usually CMC grips. They come with decent double diamond patterned Cocobolo panels and the screws/bushings you need.
I bought a Commander with a set of these on it a year ago. The seller said to me, "try those before you take them off, they will shrink your groups." I doubted him, but he was in fact (1/2) right. They didn't shrink my groups, but they made it easier to make tight groups. I could shoot the same, but work less hard. Here's why (I think after a lot of testing/swapping/testing):
The slim grips reduce the width, and thus the ability of your palm and re-curved finger tips to put pressure on the grips themselves and create an across-the-sight-plane grip tension. This means more of your grip energy is focused on the front strap and back strap when you naturally form your grip. This stabilizes the gun in the fore-aft dimension, which is the angular dimension your finger on the trigger works on to disturb the sights during the trigger stroke. So, you naturally grip the gun with slim grips in a way to stabilize it better to counteract the trigger action.
All of this dawned on me after reading what Jack Weaver actually wrote about pistol shooting and accuracy, and he focused on a nice, tight, isometric fore-aft grip. This was something I was already incorporating into my grip before I got the slim gripped gun, but it made it very apparent. So, I feel that if you think you need slim grips, not only will it make you feel better it can help you shoot better. A set of the CMC grips are attractive and not terribly expensive; try a set.
