I've got a 2010 d22. I got it new, and reckon that for the money they are hard to beat. The stock suspension is just fair, and an upgrade is the best mod I have done. You can get a 50mm lift at the front, but yep, the bump stops limit much more. You can run 32" s at this height, with a little front mud flap modification! You can source after market upper control arms and get close to 75mm if that's your thing.
You have hit on something in your title, if you go with the newer Thai build, they came out with intercooler, second battery, passenger airbag. Wheras the older jap builds did not. There is a perception that the jap builds are a better build finish. Not sure, I think that might be a bit ford v holden...
I would say the 2.5 performs fairly well with a load. I tow my camper which fully loaded would probably be close to the tonne. And find it drives ok under that load. When I go camping with a full load in the back including 50 l fridge, and camping gear for me and my two sons, I have a ply drawer system and 60 l water tank in the back recovery gear chainsaw etc. not sure of the total weight.
Most guys with them are getting. Around 10 l to the hundred k.
The negatives for me...
Torsion bar ride, Need to chip and exhaust to get better power figures, small back seat, manual shift,
But these things might not bother you. That's just where I'm at, with my kids growing, and us doing longer road trips.