Well I finally got around to installing the 225# composite springs, roads are still pretty salty around here but I took a quick rip around the block. Didn't seem rough in the slightest? My Suburban rides rougher than the Challenger! (1.120" torsion bars and bilstien RCD shocks.) Rear end sits about 1/2" higher, I can't remember if it took a couple of weeks for the other ones to " settle" or not.