No real expert Rob.......but have had a MkIV since 2003.
One weak area appears to be the cylinder head.....a spate of them failed around 45,000-50,000 miles. Twas a bad batch apparently on late 02, early 03 models! (Ask Mikeinatruck......the guys a legend when it comes to the L200.....or pretty much anything mechanical! :roll:
)
Two other things to be aware of.......both only really apply if you're going to off road it! First.....the Alternator is actually mounted on the engine below the max wading depth......so sticking brushes can be a problem. Secondly the radiator is hugely over-engineered! Mine never overheated once, even at idle, in the 42 degrees plus heat of the sahra.....but drive it through some muddy puddles & it quickly clogs up!
I absolutely love mine, I'm 6'4" & have never been uncomfortable in it!
Sorry I can't be of more help! Hopefully mikeinatruck will be along sometime!
Cheers :D