I'm not easily impressed with Cars and Trucks but my 2007 ML320 CDI has greatly impressed me. The 3.2L diesel engine coupled with the 7-speed electric-shift transmission make very responsive package. On a recent 1300 mile road trip and averaged 24 MPG while driving at 75 MPH. The driver controls do take a bit of getting used to. The transmission shift lever (switch), while logical, is unconventional. Mercedes has the best ever cruise control. The Harmon Kardon sound system is great. The down side is the price of the vehicle and Ultra Low Sulfur fuel can be a bit difficult to find at times. For off-roading the standard tires will need to be replaced with something more aggressive.
Low engine and road noise. The ride is very smooth and comfortable. The handling for a vehicle of this type is very nimble. It's a joy to drive.
There is some dashboard glare in the windshield under certain light conditions. The configuration of the dashboard make it difficult to fit an aftermarket dashboard cover. No roof rack rails on a vehicle costing as much as this ? Mercedes charges $388 for the option. Yowl !