Hey Designerguy,
I have owned 91 Isuzu Trooper and the VX will outperfrom the Trooper in the dirt by quite a bit.
I had an 1964 Unimog, but this type of vehicle is in a category of its own. Esentially a highway legal tractor, portal axles, lockers, 21" of clearance and so on. It's nice to be going 75 on the freeway again rather than 45.
I have bigger tires such as the Nittos and now that I have installed Tone's scan gauge I realized that my mileage is better than I thought, after calibrating the gauge to my tire increase. I currently average 16-17mpg Hwy/city.
From Unimog to VX - a serious change in velocity - a small sacrifice in voracity.