I would second the recommendation for a 2015 4x4 short wheelbase Sprinter if you want to stick with a Class B van camper. We often travel and camp in remote BLM and USFS areas where long stretches of washboard road and high clearance traverses of washouts are common. Our current short wheelbase Sportsmobile Sprinter is actually better for backroad travel than our previous AWD Provan Tiger XL (as pictured earlier in this thread) in all ways except the occasional desire for 4wd.
The constant pounding and dirt infiltration of extended unpaved travel really does a number on traditional RV components such as externally vented water heaters, furnaces, LP refrigerators, under vehicle tanks, running boards and generators. That's why expedition van converters like Outside Van, Sportsmobile, and Van Specialities generally use internal tankage, cassette toilets, sealed combustion diesel or electric appliances, compressor refrigerators, and large AGM sealed batteries with solar charging. Anything that involves cutting holes in the side of the van or hanging below the chassis is avoided if possible.
I've noticed newer Tiger Malayan units now have sealed combustion Propex furnaces, cassette toilets, compression refrigerators and big solar packs, so they appear to have addressed the off pavement shortcomings of our older Tiger XL in a similar manner.
Of course it's a trade-off, the characteristics that make a good off-pavement vehicle run counter to the facilities expected in road cruiser with comfortable step-up running boards and full RV hookups. And the units discussed above are NOT for Jeep trails, for that you'd need the full-on Sportsmobile 4WD conversion with high articulation suspension, 33 inch wheels, pneumatic diff lockers, and similar goodies.
