Hi Joby,
I'm probably going to get shot down in flames from all the Navara owners, but i would avoid them too. We have a fleet of them at work, and after a few "incidents" we've been told not to use them in four wheel drive on the road, and not to use them off road at all (this was the main purpose of buying these vehicles, what a waste of money!!) due to them being unsuitable for such use.
Also, i don't know if you saw a report on the news a couple of months ago, where they faired very poorly in crash tests carried out. One area was on front end collisions, the leg area for front seat passengers wasn't very well protected.
I'm sure you'll find something better value for money!
Lara.