LR3s are great vehicles and very capable in stock form. But like all rovers, they require diligent maintenance. Parts are not cheap, but you can still do a lot of work yourself. There are a lot of LR3s on the market, so be picky. Find a clean one and I highly recommend the V8 especially if you are going to take it offroad. Its nice to have the extra power and depending on how many accessories you bolt-on, you will like the extra power. If you are serious about offroading, try and find an HD (heavy duty) package which has an electronically controlled locking rear diff.
A few pics of some nice LR3s in Death Valley:
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LOL, That's my old LR3! I agree generally about choosing the V8. It makes the LR3 feel a bit more nimble on the road, but the V6 is a really terrific engine, and the white LR3 pictured above happens to be one. It's also a coiler, but that's another story altogether...
Off road, the V6 certainly holds it own compared to the V8. It's more in tune with the tranny, and has a fantastically flat torque curve. It performs superbly off road, and might even give you slightly better range. Basically, don't let the engine be the deciding factor. I also agree that the locking rear diff is nice, but I too would not let that be the deciding factor. The traction control is phenomenal, and the locker makes certain obstacles easier, but a non-locker equipped LR3 can do all the same obstacles due to its traction control. I have considerable off road experience in both locked and non-locked versions, and have never failed an obstacle in one over the other. Ever.
The add you linked to is way over priced. For a 2006, you are looking at about $15-18k for a nice clean one under 100,000 miles. These are great rigs, supremely versatile, with outstanding cargo space and passenger comfort. However, they are a bit pricey to repair when you ding them up off road
I wrote an article on shopping for a used LR3 a while back. It's a bit out of date, but still might be useful:
http://lr3tips.wordpress.com/2008/09/11/buying-a-used-lr3-v6-or-v8-which-options-cautions/
Good luck in your search!
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