I think you are comparing Apples and Pears, and the result depends on what you want to do with a car.
The 3.2 Shogun, which a lot of people on here know I am rather bias towards, is a proper 7 seater, with a decent low ratio transfer box, plus centre and rear locking diffs. With the right tyres it's very good off road.
The Merc is a completely different car that is an awful lot better on road than the Shogun and has some very clever electronics that let it perform reasonably well off road.
If you want a good tow car with proper on road manners that will cope with a slipway then the merc is probably better, throw in the odd off road trip fully loaded, want to carry more stuff, or spend more than 10% of your time on back lanes, tracks or proper off road then the Shogun will win hands down.
Personally I prefer the look of the Shogun.
Oh, and that old 2.7 lump isn't a match for the 3.2 Mitsubishi lump.
Just my opinion.
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