BMW 5 Series (2015) is 7 mm (0.28 inch) longer, 8 mm (0.31 inch) higher and has 90 liters (3.18 ft3) bigger cargo space than Buick Regal Sportback (2019).
Buick Regal Sportback (2019) is 3 mm (0.12 inch) wider and 140 kg (309 lbs) lighter than BMW 5 Series (2015).