First off, here in PA it's not legal to hunt with a semi-automatic pistol, we are forced to stick with a revolver or single shot, so the 22/45 would not have been an option. Had I been in your shoes I would have leaned heavily toward the S&W for the smooth action and the better accuracy. I have owned a single six with the .22 mag cylinder, and my son currently owns one also with the .22 mag cylinder. I have found these guns to be ever so slightly less accurate than a good .22 double action revolver. Might be the story about the barrel being slightly oversize to accommodate the .22 mag or I may have been extremely lucky with my .22 double action revolvers. That being said, I probably would have been tempted to try a new single six hunter, simply for the ability to quickly pop on a scope, especially for squirrel hunting. I believe this gun, even with a scope, would have carried quite well in a bandolier style holster,and would not affect your ability to ride in on your mountain bike.