Audi A8 (2020) is 266 mm (10.47 inch) longer and 89 mm (3.50 inch) wider than Opel Insignia Sports Tourer (2017).
Opel Insignia Sports Tourer (2017) is 39 mm (1.54 inch) higher, 733 kg (1,616 lbs) lighter and has 55 liters (1.94 ft3) bigger cargo space than Audi A8 (2020).