Seen this on ebay for the M90, I am sure they could do it for the m112. They don't give any real info on the gains.
http://thehighspeedlab.com//images/CatalogPages/sc4.jpg
"Our High-Tech Aerospace Rotor Coating with your ESM rotor rebuild services will maximize your superchargers performance potential. There are two distinct coatings applied. The first is for adhesion and wear-resistance. The second coating is slippery and will not galled. Compared to uncoated rotors, this special coating significantly reduces metal-to-air heat-transfer. It also gives air a much smoother surface to pass over, creating less friction, thereby requiring less supercharger drive horsepower. "
http://thehighspeedlab.com//images/CatalogPages/sc4.jpg
"Our High-Tech Aerospace Rotor Coating with your ESM rotor rebuild services will maximize your superchargers performance potential. There are two distinct coatings applied. The first is for adhesion and wear-resistance. The second coating is slippery and will not galled. Compared to uncoated rotors, this special coating significantly reduces metal-to-air heat-transfer. It also gives air a much smoother surface to pass over, creating less friction, thereby requiring less supercharger drive horsepower. "
