Buick Regal Sportback (2018) is 403 kg (888 lbs) lighter than Mercedes S-Class (2016).
Mercedes S-Class (2016) is 345 mm (13.58 inch) longer, 37 mm (1.46 inch) wider, 35 mm (1.38 inch) higher and has 30 liters (1.06 ft3) bigger cargo space than Buick Regal Sportback (2018).