My wife's 96 got an earlier version of the Sonoran Steel 1.2 kit that came with Bilstein 5100's for the rear (and front too).
4 or 5 years later my '99 got the newer version of the 1.2 kit, which came with stock LC Tokico shocks (and the Radflo fronts).
I really on't have a ton of miles on my OEM Tokico's yet, but since they generally last 150K-ish miles on an FJ80, I have high expectations for them.
But the Bil 5100's on my wife's car? They started leaking a little fluid by about 30 - 35K miles (???) and were pretty much shot and in need of replacement by 45K or so, she replaced them with some stock Tokico's as well, at Steve's (Sonoran Steel) suggestion. They're working great now as well, but again, no way to tell how long they will last.
So out of all of that all I can say is that the Bil 5100's wore out far sooner than would be expected, and the ride and flex out of either is fine.