I own two of 'em, earlier Freightliner-badged models. They're in ambulance service, and each racks up over 100K miles annually. I have a lot of experience and opinions about these units.
First, I wouldn't buy another for commercial duty. That said, I'd consider one for personal use. In contrast to the Fords that comprise the rest of our fleet, these highly-engineered Teutonic wonders are built like spacecraft rather than like trucks. Our guys have battered the shit out of 'em through daily use...sheetmetal is all dented from hands slamming doors, door handles pulled off, controls broken, doors literally falling off the hinges. The Fords get ridden hard, too, but are much stouter and require much less upkeep.
Second, the vaunted Mercedes drivetrains really let us down. Our Fords go hundreds of thousands of miles without problems or major maintenance (well, after we sorted out all the crap E40D trannies in the early '90's). These things both went through complete engines and trannies in the first 100K miles! No diesel should do that, much less a commercial van. These aren't even in front-line 911 duty, either. They clock miles doing mostly long-distance runs...easy duty. Dodge did acknowledge some partial responsibility and cut us a check for a portion of the work.
When things go wrong...little things, like headlights and tail lamps...it's a major PITA to fix them. We feel that they're over-engineered and underbuilt for commercial service.
OTH, they are nicely powered, get good fuel economy (21 mpg pushing a raised top and lightbars fore and aft), handle nicely, turn practically in their own length, and show very nice fit and finish. They are NOT plush at all, but clearly built for commercial service. That's why we've been disappointed in them. Others have enjoyed great success with them, but it's the fleet managers that have the real perspective on these things. Overall cost of ownership, in our experience, has been outrageous. You can buy an awful lot of damned diesel for the price of a new MB 5-cyl turbo diesel and transmission!
Be kind whenever possible. It is always possible.
-the Dalai Lama