I'm running the GoodYear Marathon tire now as the Transmaster slowly wear out. Transmaster were Load Range E @ 110 psi. The Marathons are Load Range D @ 85 psi. Both 235 75R 15's, 5 ply (2 poly, 2 steel and 1 nylon)
The Load Range D Marathons are 2540 Lb load. and the E Transmasters were 2830 lb load.
If you do a Google search for trailer tires and horror stories you'll see a lot of Carlisle stories from some time back. Their quality issues may be resolved now. And it you have a decent dealer to back them up and they are a better price, go for it. The safe bet would be Marathons in my book. You don't see any quality issues with GoodYears in all the stories.
P.S. Bryce has also got Marathons on his with no issues.
Back to the bearings....Here's a picture of why I think #3500 bearings are your future Achilles heel.
For reference the outer bearing shaft diameter on the #3500 is 1".
Just think that if you vehicle is sitting on 60's bearings, should the trailer that holding it be on such small bearings?