I need a new set of grips for a 657 Mountain Gun and have narrowed it down to either the Ahrends Retro Combat or the Tactical Fingergroove. It appears the Retro has the half moon cutout on the left side vs just a bevel on the Tactical. The Retro also looks to have a more rounded base. Either would be in the round to square butt conversion. The gun will be used for general field carry and occasional concealed carry. Has anyone handled both that can give a field report? Thanks in advance.