Our Class C's original M&S (no "2") set of tires only had a 60,000 mile warranty, and their tread wear was very little when we got rid of them - but the sidewall cracking was not acceptable. That's why we replaced them with a new set of M&S2 Michelin tires, and the ride and handling of the M&S2 tires has been superb.
We changed sizes when we went to the M&S2 set, so we had to buy seven(7) of them for our Class C.
For what it's worth:
- Michelin's M&S2 tires carry a 70,000 mile warranty.
- The new size of Michelin's M&S2 tires we had put on are Green X rated, which means less rolling friction - which maybe means slightly better gas mileage.
- The sidewall materials used in the M&S2 are different than what were used in the M&S and I'm hoping that the reason for this was, at least partially, to reduce or eliminate the premature sidewall cracking that was present in their M&S tire.