The SAE ratings for motor oils include materials testing, the wet belt in these engines have to be made of materials that are included in SAE testing and are compatible with all SAE rated oils. None of the rated motor oils will cause the wet belt to wear out faster than motorcraft oil.
I know it's an old thread but just if anyone is wondering, I got a Raptor below invoice from Buster Miles Ford, in Alabama near the Georgia border. No negotiating, they haven't had a Raptor in since I bought mine that I've seen, but they do have other trims.