IMO, a lot of the chatter about the DSSV's performing poorly, is likely due to people who are looking for a justification to spend money on fancy new shocks. This is a pretty common thing in the automotive performance market. You can buy any car, a BMW M3 or a 911, and get guys finding reasons to spend a small fortune on smaller mods. And some of what you are seeing might be from the aftermarket companies trying to create a market for their products.
I mean, I see guys saying that the brakes on these trucks are no good and replacing them with aftermarket brakes. That's ridiculous. It has 4-piston front calipers, better pedal feel than anything short of a serious performance car, and I have no problem at all locking up the tires with 33" tires, so they don't lack power, either.
Either that, or also because guys are abusing the trucks or simply expecting too much from it. It's not a Raptor. It's not a pre-runner. It's for sure not a trophy truck. But I've seen plenty of guys jumping them. Or commenting here, even, about overheating in the whoops. It was never designed for that. Now, if you want to do that, fine, and I'm sure some different off-road performance shocks may suit you better. But it's not reasonable to say that the DSSV's are deficient. Leaking seals excepted, which may be an issue though... touch wood... mine aren't yet.
I find that the DSSV's offer a really incredible balance of on-road ride quality and performance, while still working well in most off-road situations. Particularly, the spool valve allows a much flatter force-velocity curve that you can get from a disk valve shock. Results in less head-toss off-road, while still controlling things on your typical dirt road.
I'm not saying the shocks are perfect. But they're very, very good for the intended application, and I think the commentary online that they are crap, is just overblown.