If you're going trail only on tougher trails (steep climbs, ledges) don't do SR. Its mostly for rigs with heavily arched springs. It opens a whole bunch of cans of worms, driveshaft travel, fender clearance, axle walking out). Flatter spring over leafs don't need it.
Drive shaft will separate going up steep inclines unless you have a long travel shaft, or you limit the travel. On compression mine would get into my cut out fenders when I would stuff the tire. and that's with 3.5 lift and spring over.