Ever wondered what an all-electric BMW M car would be like? Wonder no more, it’s here. It’s the i4 M50, the first battery-powered machine from the division that’s given us such petrol-powered performance heroes as the M3 and M5. In the mould of those cars, can the M50 really set the standard as the quintessential drivers’ sedan for an electric world? Is it in short a true M car?