Here's a radical approach to engine oil selection...
If it's in the correct weight range called for my the engine manufacturer, AND
If it meets or exceeds the API or other standard specs (CJ-4, for example) called for my the engine manufacturer, AND
It is a reputable oil manufacturer, THEN
I doubt anyone, anywhere, can show that an engine failed because they used Delo instead of Rotella, or instead of Castrol, or instead of Valvoline.