LTX M/S2 vs XPS Ribs/Recall

When I called Michelin regarding the recent recall of LTX MS tires, I asked if I could replace my tires with XPS Ribs covered by the recall despite them being more expensive. They said I could. I`m not sure that can be correct as the LTX M/S2 seems to be the tire most people are getting. Also it seems too good to be true. Is the XPS Rib that much of a better tire than the LTX M/S2 for a 30ft Class C?