BMW 8 Series (G15) (2020) is 207 mm (8.15 inch) longer and 20 mm (0.79 inch) wider than Buick Envision (2021).
Buick Envision (2021) is 300 mm (11.81 inch) higher, 40 kg (88 lbs) lighter and has 294 liters (10.38 ft3) bigger cargo space than BMW 8 Series (G15) (2020).
