Test drive: DS 4 refines its latest model with a quietly efficient plug-in hybrid

With its lower, sleeker, hatchback style and a little bit of extra ride height for the suspension, the DS 4 is a wonderfully comfortable drive that keeps fuel consumption low

The DS 4: the luxury plug-in hybrid hatchback aiming to take on German rivals such as the Audi Q3 and BMW X1 and X2