In my own opinion, the best off road, is a short wheel base Defender. But given that the majority of users will never test it to one half of its capeability, it leaves you with many other viable options.
Most of the stuff mentioned on this thread will be a good compromise. The two things you cant compromise on are tyres and ground clearance. If you ground out..you aint going forward, if you loose grip..you aint going forward. The other things toconsider on the real tough stuff are departure and approach angles, where the shorter vehicle with the least overhang will always be better.
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