I've been interested in the Maxxis UE-168 as a LT replacement for the 14" ST tires that came with my trailer. The original tires were Trail America ST 205/75R14. After one year I upgraded to the Max...
"Thus, the loading is 3% higher based on rated load and this slight advantage goes to the ST tire. However, the LT tire is tested at significantly higher velocities (nearly 100 mph!) when compared to a ST tire. This is a 16% advantage to the LT tire. Thus, again the overall test for the LT is more rigorous than the ST test."
When I plan to run 100 mph, I'll definitely have LT tires or better. Until then, I'll just run the best 15" tires I can buy.