I would just buy from a manufacturer that makes a tire in the size/rating needed. There are several new style, cooler running, higher speed rated tires out there, that have been time proven, with good reviews. My FW came with 225/75/15 D rated Provider tires. They have been a great newer designed ST tire, with excellent reviews. Another choice, Carlisle HD. Both are good choices, available in your size, and D rating, at a better price than the GYs.
If you want the E rated GY tires, they seem to be getting good reviews from some early owners. Time will tell, I hope they will prove to be a quality ST.
Jerry