Ramble on! Thanks for the perspective from the upper end of my size range.Just a couple of thoughts:
My only point of reference with the 100 is my stock 2001 LC with 285/75r16 KO2's. (previous owner installed) I find the truck has adequate power (and more than my previous rig, a '00 LR Disco II) handles well and rides very good, IMO. No complaints with a off road performance. The 33's fill the wheel wells and suit the truck nicely. If I had to throw a negative out, I'd say the steering feels a bit heavy, but it's not bothersome and I have no other point of reference with the 100 so it could be normal.
As mentioned above, my previous rig was a '00 LR Disco II. My dad bought it new in late 99. It eventually became mine and I ran it for the next 18+ years. We ran the factory 255's, went skinny with 235's (Bridgestone Dueler Revo) and eventually went to 265/75r16 after I put a 2" lift on it. Looking back, the truck really performed well on the 235's. Ride, handling and power really went to crap after the lift. (Truck was underpowered to start with)
Excuse my ramblings, but I say all of that to say that having had 33's I'm not willing to go smaller on my 100 as the size suits the truck so well. I'm very intrigued by the 255/85r16 and the alleged performance gains, but I'm not sure the "juice is worth the squeeze" considering I'm satisfied with my 100's current performance and the additional cost and lack of AT options when it comes to the 255.