If the RV is new to you, unless you have done this already, I'd find a chassis shop to review and service the chassis./driveline components to insure all is well there. Then Michelin or Toyo (less expensive). I'd stay with a RV specific tire. The RV type tires are designed with extra UV protectant to avoid early cracking while sitting around in the UV rays. This tip came directly from an experienced Bridgestone Tire Manufacturing Engineer.
Typically Class 8 trucks do not worry about UV damage as they will go through tires much faster than any RV.