BMW 5 Series Touring (2018) is 151 mm (5.94 inch) longer, 35 mm (1.38 inch) wider, 100 mm (3.94 inch) higher and has 60 liters (2.12 ft3) bigger cargo space than Kia Optima (2015).
Kia Optima (2015) is 356 kg (785 lbs) lighter than BMW 5 Series Touring (2018).