There are several of us who can help you with leather, but for what you are asking Greg, I would drop Dwayne a note. He is working on all sorts of stuff like that. I have yet to attempt a pin lock, but I favor them for retention. As far as kydex is concerned the real pros are Okuden and David Brown. It all depends on the sort of fit you want. David uses more of a friction retention set up and Oku does a form fit retention method, which is the same way I do all of mine. I think it is a matter of personal preference.