The 2010 Mercedes-Benz M-Class SUV is a far cry from the original model. Whereas the first M-Class featured body-on-frame construction, today's ML employs a unit-body design. This creates a stiffer chassis, which helps eliminate rattles and vibration as well as quiets the interior. The design also allows for a more sophisticated suspension, yielding better handling and a more civilized ride. Although it can seat five, the ML is most comfortable with four passengers. It offers a modest cargo bay of 29.4 cubic feet, which is more space than an Infiniti FX35, but less than offered by the Acura MDX. Although rival BMW also offers a diesel option for its X5, The M-Class' BlueTEC diesel engine option is fairly unique in this class and is capable of meeting all 50 state's stringent emissions standards.