I wanted to try something different and had my upper and lower receiver nickel coated. I heard good things about Mahovsky (Hard Chrome Plating & Electroless Nickel Plating, Armalloy & Gun Bluing by Mahovsky's Metalife) so I figured I would use him. When I talked to him, he tried to discourage me from using this on a ar15 receiver since he said it wouldnt hold up well, but I tried it out anyways. 3000 rounds later and no problems with cracking, flaking, or discoloration. I did notice slight wearing where the bcg rails contact the upper. what are other's results? I see some people are np3 coating which I believe is just electroless nickel via robar.