The tread compound lasts forever. The problem I've had is that I can't wear the tread out before the casing breaks a belt or the sidewall cracks from age. Plus, the "green diamond" inserts made them the best winter mud-terrain. I also liked the oversize remolding they offered that made the tires an inch taller. They also have a cool new pattern that looks just like the MT/R. So all that and half the price of new seems hard to beat...BUT...it's all useless now. They dropped the 37s (hummer retreads), then dropped the 35s, now they are phasing out 33s.
I don't know of anything equivalent. The only retreads I see now for light trucks are on 37x12.5x16.5 hummer radials. I've had to replace a couple of the treadwrights and the tread pattern is matched fine with a Dunlop mud rover, but the diameter is different. As you all know 4WD is only fun on icy roads when your tires are all the same size (or you have a differential in the t-case).