Between me and my mechanic we were "experts" with the results I've seen up close. I'd be more concerned with actual real world problems connected with a certain brand or concoction resulting in engine failure or a consistent issue with a component like say a turbo failure directly being a result of the oil.
I just know M1 did it's job going from an engine temp of less than 200F to a turbo exceeding temps of 1000+ under load so that was good enough proof for me but it was the only time I was changing synthetic with a 3500 mile interval due to severe duty but generally with my other cars it's about every 10 months but never longer than 8000 miles which is well within my comfort zone.
'12 Focus Red Candy SE Sport 5 spd
'99 Toyota 4Runner Sport
'11 Subaru WRX STI Hatch