On the flight out to Kelowna, British Columbia, Canada, I thought I had a pretty good idea of what to expect on theMercedes-Benz Sprinter 4x4 launch. I figured I'd drive down gravel and dirt roads, and then I'd take a Sprinter on a brief, pre-planned, crawling off-road course with Mercedes guides helping me along, Perrier water and fresh pastries at every third checkpoint. I've done off-road drives before, and while...