If you really want to get into the weeds on things like oil and filters visit a dedicated forum like Bob's the oil guy and do some reading on there. There was an extensive test done on there a few years back where thousands of Subaru owners (Highly stressed turbocharged motors) collected data of all their vehicles, they used various popular and expensive oils and filters in the test, Royal Purple, Mobile One, all the way down to Rotella. They did this by documenting and sending each used sample to be analyzed by a lab for such things as iron content which would indicate wear.
What they found out was the ALL the oils were within an almost undistinguishable level of each other, with one of the cheapest oils, Rotella out performing the most expensive oils, and Mobile One and Royal Purple actually underperforming most of the other oils.
Good information here. Bobistheoilguy.com is certainly the leading internet source on oil & filter info. I've been a member there for years and have read extensively there. That website attracts some extremely arrogant know it alls who are surely mechanically inclined but will tolerate no opinion other than their own. However, here's the surprising thing: the folks on Bobistheoilguy.com are quite positive on WM brand SuperTech oil and even SuperTech filters for the most part.
