BMW 3 Series Gran Turismo (2021) is 54 mm (2.13 inch) higher, 162 kg (357 lbs) lighter and has 51 liters (1.80 ft3) bigger cargo space than Buick Regal Sportback (2020).
Buick Regal Sportback (2020) is 74 mm (2.91 inch) longer and 33 mm (1.30 inch) wider than BMW 3 Series Gran Turismo (2021).