Land Cruiser 80s are AWESOME rigs...but I would recommend doing some serious research ahead of time. There is a lot to learn before buying one, including what years are best for your purposes and some of things that will needed to maintain them and the cost ownership. Not the least of which is gas mileage. They all suck horribly when it comes to gas mileage.
I have some info on my own Land Cruiser FZJ80 page:
http://www.brian894x4.com/ExpeditionLandCruiserFZJ80.htmlI personally would not buy a 1991, 1992 land cruiser unless the price was extremely cheap and you wanted it mainly as a trail rig or preferred the old 3FE engine for it's lack of headgasket and other minor issues found on the 1FZ.
They're fine rigs, but pretty underpowered and the worst gas mileage of the 80 series line up.
The 1993-1997 rigs came with the new engine, beefier rear axle and potential of factory lockers. They also hold their value more. Ironicly, the '91/92 land cruisers sell harder than the FJ60s and even mini-trucks, even though they're stronger, beefier rigs. It's sort of a perception thing.
Prices on all 80 series rigs are falling like rocks, due to the gas price situation and unpopularity of SUVs. I suspect this price drop will be temporary if gas prices even come back to reasonable levels, because the 80 series is the absolute last of a breed of vehicles that will NEVER, EVER be reproduced in the future. That makes them extremely desirable.
Sort of like the FJ40. They weren't worth much in the early 1980s, but sure are now, even in junk yard condition.
So, the way I look at it, now is a great time to find one at a bargain price. $4500 for a '91/92 version used to be reasonable, but I'm not so sure at today's prices. The mileage would have be pretty low.
Personally, I'd keep my eye out for a later model, especially if you're looking for a daily driver, a expedition type rig, plan on loading it down or hauling people and gear with it.
As for the T-100, I've never owned one, but I know they were great rigs. Sort of a unique vehicle in their own right. It was the only mid-full size Toyota pick-up that was (a) made in Japan and imported here and (b) had a fully boxed 1 ton frame. If it comes with the 3.4 V-6 that would be helpeful as I understand the older 3.0 versions were a bit underpowered.
Gas mileage would be better in a T-100 likely, than a Land Cruiser, but the Land Cruiser is a true bullet proof tank.
Either one would be a good rig, but both sort of have different purposes and certainly different costs of ownerships.
Good luck.