i have run wagoneer springs, wrangler springs, stock cj rear springs, and now jc whitney 7leaf hd cj rear springs on my jeep and the cj springs have held up with less sagging and leaf bending than the others. i ran the stock cj rears for like 3 or 4 years of hard use and they worked great. when i put on the stock wranglers i sagged one of them bad the first time i flexed them real good. i also ended up bending one of them too but i really don't think that was the fault of the spring. anyway the cj springs seem to have a bit more arch, they still flex like crazy, seem to last longer without sagging, etc. like i said i have run a number of different setups and i by far have had the best luck with the rear cj's.