I had Safe-T-Plus for while, for a little more car-like on-center feel, not because I had any handling problems.
It worked, however it had a big flaw... The coil cover traps mud and causes the spring to rust. When the spring breaks, it binds inside the cover, and causes the bracket to rip the bolts from the frame. I had to have the frame repaired to re-mount the sway-bar. I now don't have a damper. If I ever put one back on, it would not be a Safe-T-Plus. RoadMaster has a similar unit, but without the rust-trapping dust cover. It looks like it would not be susceptible to the problem I had. I think I had it on for about 120,000 miles before it failed. I think they have a life-time warranty, but I didn't want to risk the same failure.