I've had both and currently have Goodyear G670's. They are OK, but if the price is the same I'd take the Michelins. My Goodyears are shwoing a minor problem known as "river wear", a band of wear along the outer edges and I'm not getting anywhere near the mileage (treadlife) that I always enjoyed with Michelins. However, most Rvers don't wear out the tire tread before it dies of old age anyway (6-7 years).
2004 American Tradition; 2013 Buick Verano
Homebase in the Ocala Nat'l Forest near Ocala, FL