I dont have any experience with them but the opinions from owners in Australia seem to vary a fair bit.The most common complaint is the noise at freeway speed because the landcruiser soundproofing isnt thick enough.I laugh at the ones that threw away the 1HZ and now complain that the chev diesel sucks a lot more juice than the toyota diesel.
The owners that approve seem to be the ones that spend more time offroad.I havent seen a single complaint about the reliability.
Every week in our local car/parts trader,there is always at least 2-3 already converted 6.2 litre landcruisers up for sale,often not long converted and well below replacement cost.
The 60 arent converted very often ,mainly 105,80 and 75 series