The E-rated, all steel construction Michelin XPS Rib has been a proven problem-solver on a lot of 5th wheels that have experienced tread separation problems. I was sufficiently impressed with their performance after having installed them on our previous 5th wheel that I just put a set on my truck (LT235/85R-16E).
Having said that, our current 5th wheel came equipped with all-steel construction, trailer specific G-rated Goodyear G614 RST tires, and I haven't had any problems with them, either. I did have a tread separation problem with the Goodyear Marathons on our first 5th wheel many years ago, and Goodyear replaced the tires and paid for the repair of the damage to the trailer.
Based on my experience, I went with the Michelins on the truck because I'd rather never have a problem in the first place than have to rely on a good warranty program to repair the damage caused by a tire problem.
JM2CW.....
Rusty