There is a fine line between leather preservation and leather integrity, as a high power competitor, and handgun competitor, things like the aforementioned Lexol, and or neats foot oil, are great for making leather supple and looking good, but bad for allowing leather to keep it's shape, and support. Too much neats foot on a sling will make it limp and lifeless, not allowing the support you need. Same thing with leather holsters, it will lose its form, become too loose, a good leather holster, will have a definite hardness to it, the shape will remain, and the stiffness, silicon allows for good retention, but once the pistol moves, it is like lightning. I love leather over Kydex, but, Kydex is king, especially if suede lined and silicon treated..