BMW 4 Series (2020) is 222 mm (8.74 inch) longer, 94 mm (3.70 inch) higher, 45 kg (99 lbs) lighter and has 90 liters (3.18 ft3) bigger cargo space than Mercedes AMG GT (2015).
Mercedes AMG GT (2015) is 87 mm (3.43 inch) wider than BMW 4 Series (2020).