I know cost is a major consideration for all things RV but when it comes to safety for my family and others on the road, I never have felt that (and boy am I tight with the pennies) tires are where I want to save money. Only a few square inches of rubber on each wheel is in contact with the road. Those six points of contact could represent my life. I am gonna buy the best tires and save money on something else. Buy cheap beer, boxed wine, whatever. But I am not going to scrimp on tires.
Tread, sidewall structure and stiffness, manufacturing processes all come into play for me and I think there is more than one good brand available out there. Since the pros use Michelin, so do I.
Paul