BMW 8 Series (G15) (2020) 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 (2018).
Mercedes AMG GT (2018) is 37 mm (1.46 inch) wider and 179 kg (395 lbs) lighter than BMW 8 Series (G15) (2020).