Carlos Lago returns to the Hyundai Proving Grounds to try out Cadillac's new, twin-turbo CTS Vsport, which might be one of the automaker's best products yet. With a low curb weight and a boosted 3.6-liter V-6 producing around 420 hp and 430 lb-ft of torque, will this Cadillac send the German engineers back to the drawing board?