I run GY Marathons, OEM tire on my previous and current TT. The only flats I had where on the previous TT with LRC 14" Marathon's. They where legit flats on some very rocky/nasty roads so I can hardly blame the tire.
They do wear quickly how I use the camper, lots of dirt. But are a good tire for me.
GY also released a service bulletin this spring that allows 10psi extra to be added to the tire and that raises the speed limit from 65 to 75, nice if you plan to drive that fast.
https://www.tirerack.com/images/tires/goodyear/Marathon_Special_Trailer_Applications.pdf