I used Mother's Billet on a S&W 500 mag. I really wanted a chrome-like finish on it, and Mother's worked like a champ. I think I could shave in the reflection, and no machine marks, 'rounding', etc.
As others have said before, the new finish was a fingerprint magnet, so I use a light coat of Mother's Carnuba (sp?) wax, & that has made a major difference. I can now take it out, open the cylinder, etc., (read: "show it off") without getting it covered with fingerprint smudges.
I have put a hundred rounds or so through her since the finish change. I've had no problems with burning or rusting. I got the finish I would have paid for without the cost of having a Smithy do it with a wheel.