First off-- I know nothing when it comes to this stuff.

Which is more reliable over a couple hundred thousand miles of constant beating... KDSS or Bilstein shocks?

The Trail Premium has KDSS as an option... and the TRD Pro comes with the Bilstein monotube shocks.

I watched the KDSS video and read some reviews and it sounds like KDSS is a good system. I just bought a TRD Pro and took it through some real bumpy and washed out stuff and it felt great going through the bumps (it also felt solid, true, and smooth on the highway at 80-- which I was surprised).

So now I'm wondering whats the reliable choice for antijitter long driving when frequently driving down a 100 miles of logging roads.
KDSS or the Bilstein shocks?

Well you have shocks / struts with or without the KDSS, and no, the shocks will not last 200k miles They last as long as normal shocks last. MAYBE 100k if you were really gentle on them, though I had a bilstein start to leak at about 20k though maybe 1000 of that offroading.

I /think/ your question should be, KDSS or no KDSS as it is an extra system that could go bad (and sometimes does before 100k)

If you want ultimate reliability then I think the answer would be no KDSS, but in either case you still have shocks to replace when they wear out (But of course they are relatively cheap)

Shocks are cheap had one leak at 5000kms, but the other three are at 250000kms! I love the trail look, hate the price and unsure of reliability of that kdds! I love Toyota, and hate you because you give me no reason to buy a new model

I was thinking the same thing and figured the shocks as a part would be relatively cheap ... And the KDSS as a system would be more expensive.
But I just wasn't sure how robust & sturdy the KDSS actually is and would it be cheap or expensive to fix.

I have been trying to find data on it... But the only thing I can find is the marketing material (which makes it sound good).

KDSS doesn't seem to break down that often, only a handful of complaints on the forum, but it is a HUGE cost (like 2500-4000?) to fix. If you ware keeping to 200k or beyond, then at some point you are likely to run into one of those repair bills. Nothing hydraulic lasts forever

When I first looked into KDSS, and whether or not I could justify the expense, I was concerned about maintenance and how often I'd be at the mercy of the not-so-local dealer. I decided that my daily drive to work is close enough to off road conditions that I would like it. The fact that it's a simple closed mechanical/hydraulic system without a computer or any electronics to manage it, helped sell me. If you look at the most troublesome systems and what goes bad first on any vehicle, it's usually electronic (excepting faulty design or manufacture).

Of course given just how little the Owner's Manual had to say about it had me worried. So over the course of about 2 weeks I read everything that I could find online about KDSS and hydraulic suspensions in general. In the end I went to great length to get a TEP w/KDSS, having little concern about the reliability of the system. Of course with anything dealer specific option, you're stuck going to the dealer to pay through the nose for a fix. All the other shops that look under the truck are merely going to scratch their heads and wonder what's that for? Here's just hoping some grease monkey changing my oil doesn't do something stupid and end up disabling it!