Let me share my experience
Got an HJ60, 3980 cc, 6 cylinder diesel engine, 415000 kms driven throughout in private use, mostly in original paint, the factors which I considered before buying it was that its an old school vehicle with no sensors and very less hassles, its like a pure mechanical machine, so considering its age she wont let you down anywhere up north by some malfunctioning of its sensors etc.
Parts are readily available from montgomery road lahore and are cheap, did all preventive maintainence from Toyota Ravi motors, put new Yokohama Geolandar AT/S and enjoying the ride.
Its giving superb fuel efficiency of 8-8.5 km/l with AC in city and 10 km/l on highway at a speed of 100km/h, although I was quite frightened by its 3980 cc in the beginning but then read alot of forums on www.ih8mud.com regaridng it usage, reliabilty and running cost.
The most enjoyable thing is that I slept in it by folding its rear seats on my recent camping trip to Rohtas fort, by folding its rear seats you get a 5'-6" x 4'-9" (bed enough for two persons) just lay your sleeping bag and you can sleep anywhere in it provided the weather is good. Its not possible in a three door.
Three door versions looks nice and its really a very well performer in offroading but when you consider its practicality for trips to northern areas it fails due to the reason that it has same engine like five door models with far less space.
Its really rough and tough machine offcourse its has not too much accessories but its like a camper vehicle, you can have plenty of luggage in it.
Whatever the vehicle you go for keep atleast 100 thousand margin for its routine maintainence incl. all oil & filter changes etc. I just came back from 2700 km journey from skardu, deosai and hunza in just 6 days from Lahore, and our journey continued upto 42 hrs continuous travel with AC with only one hour break each for breakfast, lunch and dinner etc., I really feel proud of my ride that she didn't gave any problem, really tructworthy but you need to have something without alteration and have complete preventive maintenance for such along and hectic journey.