BMW 8 Series (G15) (2018) is 297 mm (11.69 inch) longer, 52 mm (2.05 inch) higher and has 70 liters (2.47 ft3) bigger cargo space than Mercedes AMG GT (2016).
Mercedes AMG GT (2016) is 37 mm (1.46 inch) wider and 279 kg (615 lbs) lighter than BMW 8 Series (G15) (2018).