BMW i8 (2015) is 128 mm (5.04 inch) wider than Opel Astra Sports Tourer (2015).
Opel Astra Sports Tourer (2015) is 9 mm (0.35 inch) longer, 242 mm (9.53 inch) higher, 85 kg (187 lbs) lighter and has 386 liters (13.63 ft3) bigger cargo space than BMW i8 (2015).