Clay, I know that they didn't list a load range E option for me when I was looking for 35" duratracs. I'd wager that most of the duratracs that people are having issues with are "C" or maybe "D" range.
I will say that my Duratracs don't seem to balance as nicely as my Toyo's and I've got some mysterious tread damage to one (belts visible) that I'm going to have to replace. I'm pretty sure that the same damage to one of my E-rated Toyo's would not have any belts visible.