Automakers have a fascination with sportiness, even to the point of giving minivans and pickup trucks a performance slant. The SUV segment has likewise been touched by this phenomenon, and some of the results have been unremarkable. That's why the M-Class, in ML350 Bluetec form, is so refreshing: It doesn't try to be something it's not. While some of its competitors will continue to emphasize sportiness, the 2012 M-Class gives luxury shoppers a comfort-oriented option.