BMW 6 Series Gran Turismo (2018) is 248 mm (9.76 inch) longer, 41 mm (1.61 inch) higher and has 69 liters (2.44 ft3) bigger cargo space than Opel Insignia (2015).
Opel Insignia (2015) is 182 mm (7.17 inch) wider and 137 kg (302 lbs) lighter than BMW 6 Series Gran Turismo (2018).