i still have to say, mine have held up well. granted, i have not driven anything like you have Kyle, but when I do go out, it is usually three guys, a dog, and a shit load of stuff in the back of the truck (i have never been able to pack light).
average rear load in the picture attached (two riders out taking pictures at the time):
but you are right, they sag a little with all that weight, and maybe the OME SHD's are the way to go for the rear. probably should be looking at new springs for the rear anyway. did 4 loads this week of stone pavers. Each load was over 700lbs, and was just in the cargo area. no seats down. that sagged.