But with Mercedes’ engineers remotely tracking my every move, now is not the time to explore just how fast it can accelerate. Instead, we settle into a loping cruise to see just how close we can get to matching the economy figure achieved by Mercedes’ test drivers.
A digital readout display provides real-time consumption, which we try to keep as low as possible within a reasonable speed. The original plan was to run without air-con to gain an added advantage on the economy front, but with the temperature nudging 30deg C in the midday sun, we decide this isn’t such a good idea.
At typical motorway speeds, the Vision EQXX is superbly refined. Besides the hushed qualities of the electric motor, there is an almost complete lack of wind buffeting. It’s here where the rear diffuser deploys to lengthen the bodywork, reduce underbody turbulence and provide added longitudinal stability.
There are four modes of regenerative braking, activated via steering-wheel-mounted paddles. At one end of the scale, you rarely need to physically operate the brakes, even in slower corners. At the other end, the Vision EQXX rolls freely without any discernible mechanical drag for impressive distances without using any electricity at all thanks in part to its 185/65 R20 low-rolling-resistance tyres, developed specifically for the concept by Bridgestone.
The constant juggling between the different modes makes the consumption rise and fall. It’s both challenging and entertaining. From a driver’s point of view, there’s a lot to like about the dynamics.
It starts with the rearwheel drive layout. The steering is also quite weighty and surprisingly precise, while the packaging of the battery within the floor provides a low centre of gravity and with it engagingly agile, almost sporting traits to the handling. The suspension is heavily damped to ensure a constant ride height and the best possible aerodynamics.
On the typically smooth German roads we’re on, the ride is perfectly acceptable – firm but never harsh. With excellent forward vision and relatively narrow width, the Vision EQXX is easy to place on the road. For an electric car, it feels uncommonly lithe, responding immediately to every input. As we settle in for the remainder of the roughly 10-mile test drive, we notice that the concept already has more than 10,000 miles on the odometer – proof that there is real substance to its engineering. It feels right at home making progress on a variety of different roads, at both low and high speeds.