I bought our 2001 pop up used two years ago. As far as I know it still has the original tires on it. They look in good shape but just to be on the safe side I was going to replace them. The rims look in good shape too so here is the question. Should I buy tires and mount them on the original rims or should I buy tires already on a set of rims and why. The tires are 4.80x12.