Can the Mercedes-Benz S-Class retain its crown as king of the luxury car set?

It's the long reigning king of the luxury car set, but seven generations in, can the Mercedes-Benz S-Class retain its crown?

There's something special about the S-Class and it's reflected in the reverential treatment it receives amongst the top talent in Stuttgart. Mercedes may be rapidly expanding its range of models, with a fleet of crossovers and more affordable iterations attracting a younger customer cohort. Yet the brightest star in its firmament remains the S-Class.

For decades it has been a pioneer of the latest automotive innovations and luxury trends. Features like airbags, stability control systems, a plethora of driver assistance systems and even voice controls featured on S-Classes before trickling down to the rest of us. Testing an S-Class was always like gazing into the future.

These days it faces major competition, not just from its usual array of rivals, but from a set of newcomers like Tesla. Meanwhile buyers are being tempted away from saloons entirely in favour of the bigger, brasher SUVs.

Yet there’s still a level of luxury and refinement delivered by this class of saloon that simply can’t be replicated by the more rugged workmanlike SUVs, regardless of how much bling is stuck on them.

Mercedes dominates this luxury saloon market and despite vast expenditure and some bizarre "look at me" styling touches (yes BMW, we're pointing at you and that grille), the rest are merely also-rans. In the normal run of the market, the S-Class clocks in about 50 per cent of luxury saloon sales, followed by either the latest Audi A8 or BMW 7-Series, both taking roughly 20 per cent each.

Perhaps that’s why it doesn’t have to try so hard in terms of radical styling. That said, Mercedes has dropped the ball a little with its own grille. Modern safety tech require a lot of radars to be housed in the front nose. Car companies have tried various ways to disguise them behind grilles or in the bumpers. Mercedes’ attempt – a plastic square in the centre of the grille - doesn’t fit the luxury image of the car. But that feature aside, the designers at Mercedes have created a sleek luxury liner, with a coupe-like silhouette.

And the radars offer up a panacea of tech that includes the most remarkable heads-up display.

The star attraction, however, is the striking centre console 12.8-inch infotainment control screen. It dominates the cabin and the user experience is a delight. Tesla moved everything onto touchscreen several years ago, but it was a bit too stark, leaving the cabin barren, and drivers frustrated at having to flick through menus for even the most basic controls. Car firms have toyed with what to put on screen and what to leave as button controls, and the S-Class has the best mix yet.

Sharp clean graphics that are naturally intuitive, even for owners who perhaps are not the greatest enthusiasts for new gadgets or technology. Yet for early adopters, it’s still impressive. Meanwhile, the steering wheel controls all make perfect sense.

There’s a real sense of the car as concierge as well. It attempts to pre-empt your needs, with comfort functions that can be set to the individual then memorised and accessed via a fingerprint system.

The ride quality is as sublime as you’d expect, though arguably the front suspension set-up is not as sharp at tackling the toughest speed bumps in the same way that Audi’s A8 wafts over them.

For all the tech on board, the latest S-Class is simple and intuitive on the road and in this S350d guise is powered by a diesel engine that makes you regret how it has become a dirty word in the automotive world. I always preferred petrol engines to diesels, but this one is so refined and well matched to its nine-speed automatic transmission it’s the match for any petrol. Plug-in hybrids are on the way, as is a full-electric S-Class variant in the form of the new EQS. But diesel buyers will not be disappointed, and for all the power – hitting 100km/h from standstill in 6.4 seconds – it still manages an impressive 7 l/100km.

Can the S-Class diesel still survive when pitted against the EQS and its all-electric ilk? Frankly, yes. This is a global car, driven by the great and good (and occasionally evil) in the far reaches of the globe where plug-in infrastructure is still a pipe dream. There’s certainly room for this seventh generation to stay relevant for its lifetime.

Priced from €123,875, it’s not cheap, and on paper some rivals seem to beat it, but start adding features to those cars and the prices start to rocket up, while the standard specification levels on the S-Class are more than enough for most buyers.

For those of us who just peak at the S-Class for a flavour of what’s to come, the good news is that the trickle-down of tech seems to be more of a cascade these days.

The most striking and positive trend for less well-heeled motorists to note is just how much the gap has closed between this flagship and the rest of the range. The latest, C-Class, for example, now boasts the same big screen set-up as this S-Class, along with much the same safety and infotainment tech.

That’s just a reflection of the fact that in the tech space, car makers are always going to play second fiddle to the phone giants. So while the large 12.8-inch centre screen is eyecatching and impressive, owners of tablets are hardly going to be in awe at the touchscreen controls and graphics on offer.

It’s perhaps not fair, for the tech behind this car screen has to be far more robust than any tablet you may own. Those devices usually have lifespans of a few years: S-Class buyers expect this tech to work on demand – and at the same speed – for well over a decade.

This new S-Class is about more than the tech, though. It’s got style, substance and enough luxury touches to warrant the price, if this is the sort of figure to suit your motoring budget. Simply put, the S-Class is still out in front of the pack.

Lowdown: Mercedes-Benz S 350D AMG Line

Power: 2,925 cc, six-cylinder diesel putting out 286 bhp and 600Nm of torque matched with nine-speed automatic transmission
0-100 km/h: 6.4 seconds,
L/100km (mpg): 6.9 (40.9)
CO2: 181 g/km
Motor Tax: €600
Price: €123,875 as tested
Our rating: 4/5
Our verdict: Still the luxury king of the road – no surprise