I prefer the Havoline, since Chevron controls production all the way throught the process. Refining, blending, producing the add pack, packaging, everything. I may be a little paranoid, but Valvoline could get some bad product from a supplier and not realize it until it's too late.
I've always had excellent service from Chevron products. Valvoline, not so much, but that was years ago and probably not relevant now.