I have a coupla pre-lock 686s and a coupla post lock 686s. My youngest son prefers the DA trigger on the newest 686-6 plus over the 686-4 I gave him for his 18th birthday.(I bought it new). I see no real difference between any of them(nope. don't even notice the hole.) The prices quoted by the OP are high for my area, but it sounds like he's done some shopping and those are the going prices in his area. In a 686, if there is only $100 or less between new and used I'll buy new every time. Why? Because the lifetime factory warranty is only valid for the original owner. Yes, I know that S&W generally fixes newer guns regardless, but by law, they don't have to.....and at some point in time, economics and share holders will put a nix to their good heartedness.