Don't mistake Black-T for the other "baked on" finishes. There is a reason why the other finishes cost less. They simply don't do the same thing. Even when you get some wear on the high points, Black-T is still protecting the metal. It is actually impregnated into the metal during the refinishing process. Black-T is guaranteed for life. It's very slick - to the point your gun will be self-lubricating. It's easy to clean a gun that's finished in Black-T (basically you wipe your gun clean with a cloth).
My other choice would be Robar's NP3. It does everything that Black-T does, except that it's a dull gray color.