I have a M640-3 J-frame in .357 that is my daily carry. I'm looking for a good three finger set of grips that are open back strap. I tried closed back strap and closed grips bite. I figure an open back strap will fit my hand better and not bite. I realize the Battan is not a three finger but do I really need a "pinky" finger rest? I carry Hornady Critical Defense .357 ammo.