If the recently unveiled Bentley Grand Convertible concept were coming to market, it would be a direct competitor to the roughly $475,000 Rolls-Royce Phantom Drophead Coupé. The new Bentley concept features a 6.75-liter twin-turbo V-8 engine capable of extracting 530 hp and 811 ft lbs of torque. With this vehicle, Bentley combines the performance of its Mulsanne Speed with the open-air touring of its Continental GT Speed Convertible and a cabin that is swathed in two shades of leather (Linen and Beluga).
Th…