BMW 7 Series (2017) is 198 mm (7.80 inch) longer, 40 mm (1.57 inch) wider, 23 mm (0.91 inch) higher and has 45 liters (1.59 ft3) bigger cargo space than Buick Regal Sportback (2018).
Buick Regal Sportback (2018) is 58 kg (128 lbs) lighter than BMW 7 Series (2017).