Mercedes AMG GT (2014) is 76 mm (2.99 inch) wider than Opel Insignia Grand Sport (2017).
Opel Insignia Grand Sport (2017) is 351 mm (13.82 inch) longer, 166 mm (6.54 inch) higher, 280 kg (617 lbs) lighter and has 140 liters (4.94 ft3) bigger cargo space than Mercedes AMG GT (2014).