I've got a CSC Escapade trailer. It has the 4.80-12 bias ply tires. Time for replacements. Currently they're a 4 ply B load range. Plenty for a trailer when loaded is under 500 lbs. Planning trip out west in June (1300 miles one way) Gonna be hwy speeds 70-75 mph at times. Question is how many have ran a 12" bias ply tire at those speeds for extended times? Would a radial be worth the extra $$?