From everything I have read they are good tires.. not sure of the size
But this is generic advice.. Weigh your coach (all 4 corners) or call RVSAFETY.com and follow the links to have it weighed.
Inflate tires to the recommended pressure for the weight they bear. NOTE the load rating on the current tires, and the new purposed tires BEFORE you buy.
IF they can not handle your load.. well. you will have a problem
I DO NOT KNOW THE LOAD RATING OF EITHER OF THE TIRES MENTIONED IN THIS THREAD. off the top of my heqd.