AK9, I offer both in my shop. I don't do the chroming myself. I have an associate that does that. It's been my experience with the black chrome that it wears longer than teflon. I'm not sure about teflon permeating the metal. I've never heard it put that way before and the teflon finishes I know of are simply a coating that is baked on. You can e-mail me for details if you like. George