The price of $280.00 for a 22 inch tire sounds very low. You get what you pay for, as the saying goes. I've done a lot a research and pricing in an effort to replace my 6-7 year old Michelin XRV's 24570R19.5. On Monday, I will have 6 of them installed on my W-20....they are Michelin XZE's, which is a better tire than the XRV and the cost for each tire is $330.00 plus balancing, installation, new steel valves, FET, etc. Three other dealers in the area were in the ball park with the price. Camping World was a tad higher for XRV's. I didn't ask CG for a price on XZE's. So, as I said, you get what you pay for. Years ago, we had a 28 foot class C and bought "inespensive" tires for it. Had three blow outs inside a year!
Hope this helps and I'm not trying to bash Dayco but relate my experience.
2012 Tiffin Allegro 34 TGA
Ford V-10 22000 lb chassis
Brake Buddy Advantage,