I'd buy truck tires, seems the rubber lasts longer than the RV tires and cost less than 1/2. I've been running them for a while now. Got 11 years of the first set, and am on 7 years on this set. I only got about 3 years out of the Mich's. Dry rot seems to be the biggest factor in both cases. Truck tires, 19's run about $1600 a set, Mich's were $3600 for a set. Just my experience.... but, with the truck tires you will get a bit of a bump bump on a cold morning when first starting out, but I've never had to have them rebalanced......
May your black water hose never break!