GoodYear ENDERANCE tires have been on the market for a bit over two years with a STELLAR record!
Don't want to hear the "not long enough on the market" BS. 2 plus years and no issues that I have heard of, to me that is a good record.
I have a set on my heavy 23' GlasPly boat trailer and I tow 70 a lot with ZERO issues. My son put a set on his heavy boat trailer and traveled from NW WA to TX Summer 2017 at 75 plus with ZERO issues.
Get the "E" if you want but air to actual weights plus 5psi per GY Tech when going up in load range.