I also had 2 failures of the Goodyear G614 RST tires in 2007 within 3 months of each other. The first failure did little damage, but the second resulted in $2,500 in damages to the 5th wheel, which Goodyear paid to repair and also replaced all 4 tires.
This year, with the Goodyear G614 tires approaching 3 years of age once again, I bit the bullet and also bought 5 each 17.5" aluminum wheels with 215/75 Michelin XTA tires mounted and balanced from Scott at
www.trailertiresandwheels.com . My choice of the Michelins was based on trouble-free experience with Michelin XPS Ribs on a previous 5th wheel and the fact that I've had no failures with Michelins and 4 with Goodyears. I elected to replace the spare with a 17.5" Michelin XTA since the spare was one of the original Goodyear G614 RST tires and was approaching 7 years of age. I'm quite satisfied with the new tires and wheels so far and also with the service I received from this vendor.
Rusty