Just bought our Cardinal 5er this spring, one of the selling points was that it had new Kumho tires, the seller upgraded to 16" tires and wheels. We dont have very far to go each time we go out so I wont rack up the miles on these tires. I'm sure I will get quite a few years out of them. I havent boughten a "cover" for the south facing side of the trailer yet but will this fall before it goes into strage. My shed isnt sided yet, (another project) Sun light and weather is probbly the worse factor on your tires other than road hazards.
From all I've read and seen, I will be buying Kumho's again when that time comes. Guess I'd better start putting money away for that day.