It’s a statement of engineering excellence, astounding refinement and unsurpassed technology. If perhaps for just a few months.

Price: $215,000 ($257,340 as tested)
Powertrain and economy: 3.0-litre inline six-cylinder petrol, 270kW/500Nm; nine-speed automatic transmission; four-wheel drive.
Vital statistics: 5179mm long, 1503mm high, 1954mm wide, 3106mm wheelbase. 20-inch alloy wheels.
We like: Astounding technology that will eventually filter down to the more mainstream models, total plutocrat package, sets new precedent for category.
We don’t like: Surely only sitting pretty until EQS arrives, could be too complicated for those who find even a cell phone challenging.

SUCH are the times in which we live: The latest generation of the top tick car for diplomats and tycoons is a tour-de-force that suavely takes technology, interiors and engineering to an entirely new level in its 2020 form.

And, yet, will it transpire that the mighty and magnificent S-Class enjoy but a few months’ adulation before a certain other arrives with ruthless intent to, first, push it from the spotlight and then – ultimately - put it out of business?

EQS, of course.

Mercedes-Benz has been doing S-Classes for a long time now, it has rarely done them poorly and it has never done any other car to threaten them. Until now.

By Christmas, the traditional – that is, internal combustion-engined variants just rolling in – will be joined by another kind of flagship executive car whose ultimate purpose in life is … well, let’s not underplay things. It’s bent on fratricide, pure and simple.

EQS is an S-Class in electric. And, yet, of course, it’s so much more. With a nod to Dennis Denuto, it’s the vibe. A ‘new chapter’? Pah, that sells it short. When Mercedes-Benz chief executive Ola Kallenius unveiled EQS back in April, he described it as a “defining moment” for the world’s oldest car maker.

Mercedes’ is quite open that an opus atop its first dedicated EV platform isn’t just out to set a precedent among high-end models. Equal intent is to provide buyers with a fully valid electric alternative to what’s on test today, the traditionally powered S-Class. They’ll be sold side-by-side for a while then, one day, the fossil fuel-fed line will be history.

When that’ll happen is not yet clear, and until Mercedes here delivers specs and pricing, how directly competitive an EQS might be to the S 450 4MATIC on test today is entirely speculative.

Yet evidence is mounting that a showdown would seem likely. The UK prices are out and, over there, it’s close. A local dealer told me EQS will be more than $200k. As is the S450. In base factory form, it’s a $215,000 car. This particular one pumped to $257,340, having been enhanced by $14,500 energizing and $15,500 exclusive packages, a $6500 AMG Line fit-out and $4990 digital lights. Oh, and let’s not forget tyre pressure monitoring, for $850.

Which way will those with the wherewithal ultimately steer? EQS is obviously to a wholly different design aesthetic and, of course, it plugs in to play, but electric is the future. More than that, Mercedes avows EQS will be an even better kind of S-Class experience than the S-Class delivers. Think about that when experiencing the S450 because it is, frankly, already hugely impressive.

But EQS is said to be even more of a lesson in technology and engineering detail. All this, and freedom from the shackles of Big Oil, plus the high potential of it being better insulated from the ravages of depreciation. That, the probability of the EQS being a massive magnet for attention and discussion, and – I cannot reinforce this enough – the certainty that the brand/the world is going electric means … well, it kinds makes me wonder how relevant an S-Class will be in even just a year’s time.

Of course, everything above is based on assumption actual owners think as I would. I don’t know if that’s the case. Clearly, many well-heeled people are careful with their money. Others might well want to party on with petrol. Mercedes would not have built the S-Class or the EQS without being very sure there is an audience for both.

Anyway, point is, as much as it might be on borrowed time, in the here and now it’s hard to see the S-Class as a wasted effort. Yes, it burns petrol (though not hugely – the test car averaged 10.7 litres per 100km). And, sure, there’s a reality that, no matter how impressive it is, there will come a day when it will never impress enough. Yet it’s only fair to say that, on test, the S450 nonetheless came across as being very impressive indeed.

If it’s all you want, then assuredly it’s THE car to have. Could it be the finest luxury car you can buy in this sector today? Certainly, it utterly spanks the -admittedly, much older - equivalents from those German rivals.

First impression from meeting this model is how big it isn’t. No, no a typo there. Being 34mm longer, 55mm wider and 12mm higher than the predecessor line, it is a truly large car. Parking spaces are not put to waste. Yet is also so neatly proportioned that it hides its bulk well. It’s only on getting in that you think … ah, yes, proper, stretch-out limo. And let’s remind this is the standard wheelbase model. There’s a lengthened one for plutocrats demanding extra rear legroom.

No back seat televisions, no fridge or champagne cooler but damn near everything else. It’s easier to describe what doesn’t come in this car than what does.

The highlight features are electronic and, because S-Class is traditionally the Mercedes that debuts new stuff, no surprise that among those are a swag of breakthrough capabilities.

That it really is the most advanced Benz here will doubtless be a mind-bender because, styling-wise, it is not hugely adventurous. Even with modern touches like snazzy hideaway door handles, so named because they tuck flush into the bodywork, the exterior look is very ‘traditional’ and a bit staid.

There’s just one major new functionality that’s actually a catch-up feature, this being wireless Apple Carplay/Android Auto implementation (it’s been on BMWs for several years) into the 15-speaker Burmeister sound system. A lot of other things are world debuts. So many that it’s safe to call this the Mensa Mercedes of the moment and assert that you simply won’t find more cutting-edge technology on any 2020 competitor.

Sure, there are some aspects about the car that seem almost absurdly complicated.

First up, you need understand the car is looking at you while you look at it. First involvement for a new driver is an adjustment of the instrument display to match your eye line (it offers handy alignment tips so you can position the driver’s seat perfectly to give you the best effect). It needs to get that sorted so it can then figure how to assist in what you are looking at. No, really. It’s that smart.

The seats alone reveal the exactitude of the engineering reach. These can be optioned up to carry 19 motors each, ranging from longitudinal, height, angle, backrest and head restraint adjustment to seat cushion depth and even (for the front passenger) heel support adjustment.

On top of that, there can be four vibration motors to massage each body in each seat, five fan motors, a motor for the lumbar support and another one for the adjustable side bolsters. And, yes, they are heated and ventilated.

The console-mounted touchpad has been replaced with a new MBUX menu interface on the large central 12.8 inch portrait display. Using an updated and revised implementation of MBUX, it is the major interaction point to the car. Almost everything you need is accessed from this screen.

The instrument cluster has been upgraded with the option of three-dimensional displays, and augmented reality has found its way into the head-up display, with information projected far down the road, while arrows point into thin air through the windscreen to show you which road to take off a junction, as well as its name. In conjunction, the big touch screen shows a detailed sat-nav map, which minimises to reveal a camera view of the junction ahead as you approach, with arrow pointing out the route to take.

Set the car on cruise control and it pulls the remarkable stunt of self-slowing not just for corners but actual intersections, turning demurely in the indicated direction then acceleratingly smoothly back to the pre-set pace.

More? “Hey Mercedes” voice control is very much an active accomplice. You can adapt the various ‘wellness’ features like the glassed stripes of ambient lighting, massage seats and more according to your mood. This car is all about calming the stressed-out executive. One sure way to impress passengers is to in fact say “Hey Mercedes, I’m stressed.” The car will self-adapt the cabin lighting, music and temperature, plus activate a massage programme, to aid your mental wellbeing.

The ambient lighting changes colour according to the cabin temperature you’ve set, but also has an active safety role in that it flashes as to an alert, on one side or the other depending on which crosses the line, as a lane-wandering alert. If you don’t react to that the Lane Keeping Assist uses active steering to pull you back into your lane.

Speaking of. There are at least 20 new active safety features and all are in optimal formats. Active Distance Assist prevents collisions with stationary objects at up to 130kmh, Active Evasive Steering Assist responds to cyclists and ends of tailbacks, as well as pedestrians, and works at up to 105kmh to steer the car away from an accident. The adaptive suspension raises the body up just before any collision, to take the hit on the strongest part of the chassis. Even the seat bolstering shoves the passengers away from any collision.

It has four-wheel drive, and also four-wheel steer, to diminish the turning circle. It has two front radars with 130 degrees of 'vision', a long-range front radar, a pair of rear radars, a front-facing stereo camera, a 360-degree camera and a dozen ultrasonic sensors.

Sounds complex, right? Well, yes, but some of it is self-operational and never requires human involvement and stuff that does mainly require surprisingly little learning.

The set-ups are generally so logical in their application that, basically, if you already know the fundamentals of the Benz cockpit layout, then there are no big challenges here. I never once resorted to the handbook.

The only drawback to having a touch screen is the usual gripe; it isn’t impervious to fingerprints and smudges. In bright sun, there’s a clear evidence trail of what you’ve touched swiped and tapped. You’ll need carry a soft cloth to tend to that and also the inevitable smears on the steering-wheel interfaces as they are also now all touch-sensitive. In saying that, you alternately can ask the car to do things – though, for that, you need to be precise in your commands – or simply wave a hand. Doing that near the sunroof is enough to command the blinds open or close.

All this and it’s also a car. Driving it is straightforward enough. Though in respect to that, if I could have found a way to spend all my time in the back seat rather than behind the wheel, and somehow also been able to drive the car (an impossibility - though it has some features paving the way toward autonomy, it won’t allow that), then that’s where I’d have stayed. It’s so comfortable back there.

I was surprised to find that this car had sport and sport-plus driving modes; those, to me, seem a bit out of sorts with the model type, this being the edition with a ‘mere’ three-litre in-line six. Yet that engine is, with 270kW/500Nm, more powerful than you’d think it should be and is thus quicker than it has any right to be; ripping to 100kmh in 5.1 seconds on its way to a limited top speed of 250kmh. So it can move and, when sport or sport plus is engaged, is entertaining; those modes sharpen the throttle and gearing responses, and make the cornering flatter. It handles its size really well, all in all.

What’s more impressive about the car’s ability to move quickly is that it does it without losing any dignity. For one, the car’s wonderfully fluid ride quality maintains decorum. That’s in itself is a heck of a testimony to those who have tuned the adaptive air suspension system. The ride quality is absolutely sublime; often it simply irons out road imperfections.

For all that it does a decent job when asked to move swiftly, the S450 is nonetheless at its best when driven with respect to how you imagine passengers would best enjoy it.

If I ever landed a job as a chauffeur, I’d love it to be with this car. There’s just great pleasure to be had by driving it smoothly and with measured inputs. When run with restraint it is uncannily unflustered and wonderfully refined; wind noise is not evident, even roar over coarse chip is quite well quelled and the engine is so smooth and, often, too quiet to hear.

That’s when the fuel burn is most environmentally considerate as well. The petrol models all now run an integrated starter generator (ISG), which uses a 48-volt 'mild hybrid' electric system to maximise brake energy regeneration and boosting performance by up to 16kW and 250Nm under heavy load. That’s the ‘EQ-Boost’ factor.

Mercedes-Benz claims a combined-cycle fuel thirst of 8.4L/100km, which appears very reachable at a gentle cruise. That’s impressive given the car’s 2207kg mass. The electric involvement allows Benz to use a modest capacity engine and also deliver CO2 positives. It's not zero emissions, of course, but it's not nothing.

Still, what stop it being all that you need is that it needs an engine; when we’re at the cusp of change to electric motors, does that make it the best horse to back?

Well, debate that one long and hard … but Mercedes is one of many car makers to decide to leave combustion engines behind. The reason is no whim.

Right now the world is digesting the Intergovernmental Panel on Climate Change (IPCC) report that, under all scenarios examined, says Earth is likely to reach the crucial 1.5 Celsius warming limit in the early 2030s unless we make deep cuts to CO2 and other greenhouse gas emissions.

That’s why the car world is going electric. That’s why the EQS, which will have every technology mentioned here and a bit more – including the cabin-width hyperscreen display - is unavoidably more relevant than the S-Class.

The S-Class is a titan. If the battery car proves itself to be as luxuriant, as indulgent, as incredibly engineered and well-built – the only fault, if it could be called that, during test was that the left rear outside door handle was a touch stiff in its action - and as sophisticated as the current flagship then it will surely be more than just a formidable competitor. It might be Benz’s best car ever. I can’t wait.