Mercedes GLC-Class (2015) is 264 mm (10.39 inch) longer, 89 mm (3.50 inch) wider, 364 mm (14.33 inch) higher and has 200 liters (7.06 ft3) bigger cargo space than Porsche 718 Cayman (2017).
Porsche 718 Cayman (2017) is 659 kg (1,453 lbs) lighter than Mercedes GLC-Class (2015).