I have a 2007 30' Arctic Fox 5'ver. A few years after I bought it I noticed one of my ST tires bulging out. After reading many horror stories of the ST tires blowing out I replaced them all with Mic...
The Michelin XPS Rib is a great tire. I've run them under previous 5th wheels with never a problem. Having said that, I have no idea how they are going to perform after sitting for 3 years. Good luck!!