I'm replacing my 6 year old Goodyear Marathon tires this year and still have no idea what to buy. I've never had a Goodyear failure over the 15 plus years of having them on my trailers but the Kumo's are impressive with the load range D rating on a 14" tire and a speed rating of 75 MPH. Everything else seems to be rated at load range C and 60 MPH which to me is just unrealistic.
In fairness there is a note on Tire Rack on the Goodyear Marathons stating that if speeds are increase to 75 that tire pressure should be increased by 10lbs which is what I have always done.
Then there's price. The Goodyears are significantly cheaper and more readily available than the Kumos. Still have time to figure it all out and will be watching this post to see what others have to say.....