Looking at UOA results is not bias. Watch some of The Motor Oil Geek videos on YouTube. He has no brand preference or sponsorship. Shoot, he doesn't even use oil from the brand he helped designs oils for in his personal vehicles.
As for high mileage, there are lots of people who had high mileage vehicles in the ,60s, 70s, and 80s using conventional oil without all the extra anti-weer additives and synthetic blends. so just because you were able to drive your vehicles that long on a specific oil doesn't mean it's the best oil to use. Me person, I will never run RP in any vehicle I own after seeing the inside of an engine a friend had. He did 3000 Mike oil changes using Royal Purple since the first oil change after he bought the truck. 80k miles later and after it sat in his shop for a year, I got it and opened it up. There was a purple film coating everything in the crank case and valve train. even on the dip stick to where it made it hard to see the hash marks for fill level.
