Mazda 6 Atenza (2015) is 29 mm (1.14 inch) higher and 326 kg (719 lbs) lighter than Opel Insignia Sports Tourer (2020).
Opel Insignia Sports Tourer (2020) is 638 mm (25.12 inch) longer, 88 mm (3.46 inch) wider and has 53 liters (1.87 ft3) bigger cargo space than Mazda 6 Atenza (2015).