Ok, being a total newb i went and got the 3.5 super ride kit with the HD SYE and CV rear drive, full leaf packs, being that I use mine as a DD and Delivery rig. Just joined an OHV club and took my first run a few weeks back.
I don't know how the superflex would compare, but in the forum for jeep pics put some in that will show from diff angles exactly how much flex it has on a 98. I drove down that pipe till the jeep started rocking then backed up 3" (glad I did seeing where the rf tire was starting to slip while rocking, lol).
Note that I also messed up and didn't get mine with disconnects, so that is with stock brake lines and full hooked sway up front.
I found that on highway mine seems to actually ride just a hair better with the lift and the yoko Geo at+2's, handles awesome on trail (ran cedar tree in Tillamook State Forest for 1st ever run and made it without a scratch), at low speed it's a bytch going over the 2 sets of double speedbumps in the driveway of our apts, no more taking em at 15mph for sure, but if I drop to about 5mph it's smooth as silk.
I do notice a little bit of wander with the rear sway gone, and I do get some bump steer on speedbumps. (Would a better than stock steer stabilizer help that?)
I probably won't go full out on this rig for wheeling as it is just too clean for it, and the wife has a 90 that's about to expire that I'll get from her and turn into a trail rig now that I'm hooked
I did notice that after cedar tree i had just a 1" patch of scruffing on the rear bottom part of the rr flare along the inside surface. I figure to go 4.5" cut fenders and 33 or 35's on the 90, also debating on dropping in a SB V8 since she has all but killed the 4.0
ran it oiless till it froze, then got it started after cooled down and it doesn't even smoke, but lost about 55% power.
Phew! Most I've typed in 15 minutes, lol