It depends...........
On what kind of use your RV gets.
IF you put on a LOT of miles in a year or carry an unusually heavy load, then you probably shouldn't skimp trying to save a few pennies.
OTOH, if you just go a couple of thousand miles (or less) a year, check with some truck tire shops in your area.
Action Gator Tire sold me some "off brand" ones that seem to be holding up good with my light use.....at just a little over half the price of Michelin's.
If you don't drive it much, getting "premium" tires will likely just be a waste as they will "age" out (5 to 7 years) way before the tread is used up.
Sorry I don't remember the brand and the RV isn't where I can get to it easily.