The car’s overarching smoothness, its comfortable, well-sealed cabin and the isolated feel of its controls combine with Mercedes’ full suite of active driver aids to make long-distance driving feel like something of a privilege.
Even in appalling test conditions of monsoon-like rain, the S560’s optional Distronic Plus active cruise control and active lane-keeping assist systems worked flawlessly at UK motorway speeds. Unlike so many similar systems, they’re not flummoxed by spray, dazzle or waterlogged sensors, providing reassurance just when it’s most needed.
The S560’s ride prsents a couple of relatively minor disappointments. There's a little more road noise and surface patter that filter into the cabin than you’d ideally like — and enough, certainly, to be a good advert for the car’s standard-fit 19in rims (our test car was on optional 20in wheels). But it deals very well with the majority of UK road surfaces by cleverly cradling the car’s mass and very effectively rounding off the edges from the vast majority of bumps and ridges you might come across on your evening commute.
Mercedes Magic Body Control suspension leaves a particular impression as it works away underneath you, feeling not quite like air suspension and yet not quite like a well-tuned passive steel coil suspension set-up either.
Even though the car’s chassis rates are always adjusting to be ready for intrusions they’re about to encounter, they do it imperceptibly — and so there’s a clearer sense of honesty and predictability about the relationship between the road and the car’s sprung and unsprung masses than you'd get with air suspension. Better shock absorption, too, and better on-centre steering feel.
And yet certain short, sharp ridges still seem to catch the car’s suspension unawares — the car being much better at ironing flat a set of low-frequency, low-amplitude undulations. Mercedes’ latest and greatest suspension system clearly can’t be ready for absolutely everything. The S560’s ‘curve tilting’ function is handled like an extra setting on the car’s drive mode toggle switch and, you sense, would be at its best on those long, sweeping bends of European dual carriageways taken at continent-crossing speeds.
You get a flavour of what it does well on some UK motorway sliproads, because it inclines the car gently into each bend as you turn in, preventing lateral cornering loads from acting on the cabin occupants with notable success. But try to use it on a typical British A-road and you’ll find it slow to react at times, and that tends to rob the S560 of initial steering weight, making each turn of the wheel feel oddly vague; a bit like pushing at a door that’s come loose at the hinges.
Thankfully, steering weight is much better when you simply turn the system off.