Valvoline VR-1 which they did not test contains high amounts (1200 ppm as compared to 800 ppm) of
zinc and phosphorous, which all
oil did until the EPA felt the
zinc and phosphoruos damages catalytic converters.
We pressured the Mobil engineer into why the RP performed better in this test and that is the reply we were given. I asked did the corrosion occur over 1 year or 20 years and did not get a definitive answer. RP is an incredible story they obtain their PAO from the plant next to us and add some additives and botte it. There whole operation is about the 1/4 the size of a standard walmart. Shows you what advertising can do. The size of Mobil compared to RP is like comparing the size of the earth to a volleyball. NOT THAT BIG IS BETTER.
Their lab employs about 10 people, with one guy being the brains of the operation and I think he actually invented it. Just North of Houston. They originally supplied lubricant to offshore platforms, a customer wanted to a unique color to tell if his equipment was leaking the lubricant, voila they made it purple.
I have used royal purple and have had great luck with it in my cars and at work. It is application specific. I have also used Mobil and have great luck with it. 99% of bearing failures are attributed to contamination, improper installation, lack of lubrican, very very very rare is it ever due to lubricant failure.