McLaren GT (2020) is 392 mm (15.43 inch) longer, 315 mm (12.40 inch) wider and has 79 liters (2.79 ft3) bigger cargo space than Mercedes A-Class (2015).
Mercedes A-Class (2015) is 219 mm (8.62 inch) higher and 176 kg (388 lbs) lighter than McLaren GT (2020).