zinc oil useage?

I said I would contact the tech guy at Shell the maker of Rotella, and ask about MY case of using conventional Rotella T4 15-40. I told him I am not a RACER, I use premium pump gas, no alcohol, I just don't want to not damage my engine. He said that is their product he recommends.
So it will work for me as it has been.
Is there a better flat tappet oil? Maybe so/ Could I afford it. Maybe...mayne not!