Kia Optima Sportswagon (2015) is 51 mm (2.01 inch) longer and 600 kg (1,323 lbs) lighter than Mercedes M-Class (2015).
Mercedes M-Class (2015) is 66 mm (2.60 inch) wider, 318 mm (12.52 inch) higher and has 137 liters (4.84 ft3) bigger cargo space than Kia Optima Sportswagon (2015).