I used to run bronco springs on the back of a 95 nissan pathfinder I had.
They were a bit too stiff for my liking. Maybe with more weight in the rear they might be ok for a ride. In this application I guess ride quality doesn't really matter since it's a trail rig.
I got the superflex series, there supposed to be alot softer, than a stock or the superlift springs. plus I have the cab moved back and the spare tire, gas tank, dual batterys , moved as far as back as possible. so I'm hoping thats not the case.