BMW 5 Series (2018) is 46 mm (1.81 inch) longer, 4 mm (0.16 inch) wider, 44 mm (1.73 inch) higher and has 79 liters (2.79 ft3) bigger cargo space than Opel Insignia Grand Sport (2017).
Opel Insignia Grand Sport (2017) is 350 kg (772 lbs) lighter than BMW 5 Series (2018).