While the Mercedes S-Class has remained the top luxury saloon, it has recently started to show its age.

But now (all those well-heeled people will be glad to hear) there’s a new, freshened-up model with more autonomous tech and an obscene amount of onboard luxury – who knew the one thing lacking in 21st-century motoring was a wellness programme?

At the touch of the Wellness button, this S-Class transforms itself into the ultimate mobile chill-out zone. Mood lighting and reclining seats set the tone. The climate control then adjusts the airflow, as if a summer breeze were blowing across an open meadow, before a built-in massaging unit applies a pummel worthy of a bare-chested Turkish masseuse.

This luxury doesn’t come cheap

This piece of automotive nonsense, which defies you not to become its guilty pleasure, is part of the £6,695 Premium Plus package. This is the top spec car, which builds on the S-Class’s sole trim-level, the AMG-Line, and incrementally adds further equipment until you’re way past the point of remembering that the standard car doesn’t actually need any of this extra stuff after all.

As the base car (a term used in the loosest possible sense), the S350d costs north of £72,000. Take it as the range-topping S65 and that figure rises to an eye-watering £187,240 ? which is Bentley Flying Spur territory, and then some. The differences between the packages are very discreet, though, and unless you knew the powered roller blinds were missing or the rear head restraints were slightly less squishy, would you really notice – or care? Probably not.

Intertior

It still features the same 12.3in colour touchscreen with COMMAND Online, Mercedes’ 24/7 concierge service, found in the rest of the range, plus AMG alloys and a AMG body-kit, leather seats, a multifunctional steering wheel with touch control pads and 64 shades of cabin lighting.

It too receives the next level of autonomous driving, which uses GPS and onboard data to steer itself through the murkiest of weathers. It’ll even remotely self-park itself via a smartphone app, which is a bit daunting the first time it reverses itself into a parking space, the width of a cigarette paper allowed for error.  

Can you come back to drive the diesel?

Unfortunately, the S350d ? the divertive that premiers a new in-line six-cylinder diesel engine and the model that is expected to account for most UK sales ? wasn’t available on the recent press junket.

Side

So the best we can say about it comes from the Mercedes handout, which suggests a very respectful fuel efficiency of 52.3mpg and 139g/km of CO2 emissions. It also claims a 0?62mph time of six seconds and a top speed of 155mph.

However, since it wasn’t there we stepped inside the S500 and S65 and tested those instead. It may seem a good idea to plant a 6.0-litre V12 bi-turbo under the bonnet of the S-Class, yet in reality in doesn’t quite work.

Less power, more respect, if you please

Unquestionably, the best place to be sat in the S-Class is in the rear; stretched-out and being soothed by whale music. What you don’t need is a dirty great thump of torque just as the Turkish massage gets into its stride. And it’s not that much faster than the S500, either. While the S65 reaches 0?62mph in 4.3 seconds, its 3.0-litre petrol brother does it in 4.8 seconds – and with so much more reverence, too.

The sports suspension and anti-body tilt system (optional) makes the S65 seem a little more nimble, but why on God’s Earth would you even consider taking it anywhere near its handling limit in the first place? Unless you’re planning on being chased (or the one doing the chasing) stick with the S500 and bolt on the premium package. Anymore power becomes a wasted commodity.

Rear

A new set of ultra-bright, multi-beam LED highlights means the front has been restyled. These changes haven’t affected the S-Class’s overall external measurements or huge boot space.

As a comprehensive executive limousine package, the S-Class still trumps over the Audi A8 and BMW 7 Series, for just how long remains to be seen.