A little late now, but the reason that I went with the 5165's was the West's endless miles of washboard roads. My family calls them "4-40 Roads." You either go 4 MPH or you go 40 MPH (though I know of a couple 7-70's in NV... ). Absolute key to going 40 is vehicle control, and that needs shocks that won't fade. While I have to punish my live front axle Toyota pretty hard to fade it's 5100's, I figured that this CTD's much heavier live front axle and wheels/tires would make it far easier to fade them. With IFS you don't have nearly as much unsprung weight so it should be a lot harder to fade the 5100's.