Mercedes-Benz S 500 L 2015 Review

"Let's keep this car forever." Those were the words of the most junior member of the family, settled back in the rear of the Mercedes S 500 L as he was, enjoying meta-loungeroom luxury on the move.

The teenage hedonist was delighted by the legroom and headroom, the finer control of the ambient temperature, the power-adjustable rear seats – complete with three-position memory as well – and two tablets and a DVD slot for kids or young-at-heart adults.

The Mercedes was roundly applauded by the whole family during its brief stay with us. Seat comfort was the long-wheelbase sedan's forte, but NVH also earned praise, as did ride quality and the climate-control system, which featured face-level vents located in the centre console and in the B pillars for the rear-seat occupants.

While the S 500 L will seat five, the squab for the centre rear seat position also folds down to form armrests with two built-in cup holders for the two outboard positions. The older child admitted to falling asleep in the back of the S 500 L on the 10-minute trip to school one morning.

That's a sign indeed that the S-Class is a very relaxing car.

Just like the S 63 AMG coupe we reviewed a few months back, the front seats in the S 500 L are ridiculously enveloping and the headrests are the softest I've ever encountered.

The S 500 on test was trimmed in attractive two-tone leather and woodgrain veneer for the dash and steering wheel. While it presents very traditionally during the day – if you look past the flowing form of the dashboard and centre console – the ambient lighting at night lends it a sci-fi edge. It's adjustable for different colours through the car's Comand system too. I opted for Twilight Purple, just to disturb the next person to get behind the wheel – colleague Feann Torr, as it turned out. At night the car's cabin lights up like a scene from 'Tron'.

There's a huge infotainment screen in the centre fascia, displaying all manner of information in high-resolution graphics. That information runs to read-outs for economy driving, satellite navigation, audio, vehicle settings and other features. Destinations can be entered in the satellite navigation system using voice control, which is very handy and easy to use.

Most comfort and convenience features could be operated by redundant controls, including trip computer and audio system switchgear on the steering wheel.

The audio volume could also be set through a scrolling knob on the centre console, and a swipe feature allows the driver to shift from one track to the next (or previous) without using the single-point controller. So if you had the satellite navigation displayed in the infotainment screen, you could also monitor the car's fuel consumption and adjust the audio system volume without taking eyes off the road (the head-up display also mimicked the satnav route instructions graphically) or changing screens/drilling down through menus.

There was a minor glitch with the Bluetooth audio streaming at the start of the week. The system briefly failed to recognise an iPhone that had already been paired, but it had righted itself by the next morning and didn't cause any further trouble for the remainder of the week. It's not the first time I've had a problem like this occur in a Mercedes of recent vintage.

The large boot of the S 500 L is deeper still by not having a spare wheel under the floor. And the boot lid is power-operated for ease of use.

Although the S 500's interior is very welcoming, drivers may not appreciate having a column shifter for the transmission on the right side of the steering column. And the Agility Select switches for the Airmatic suspension and drivetrain are located on the far side of the centre console, closer to the front-seat passenger. On the plus side, Benz's unique parking brake release is well placed on the lower right of the dash, where it won't occupy valuable real estate in the centre console or the driver's footwell.

The S-Class may be designed for comfort, but it's also exactly the sort of car you'd picture making a J-turn to get-away from RPG-wielding terrorists. Furthermore, the Mercedes musters just enough mass to push aside that imposing black SUV blocking the road ahead of it. It has the right blend of performance and dynamic ability for the heroic chauffeur to peddle hard and save his boss in the back seat from capture.

Performance is astonishing for such a large car, but you pay for it at the pump, even driven carefully. At the conclusion of several days driving around town the trip computer displayed an average consumption figure of 16.9L/100km.

The mellow V8 is very quiet until you open the taps, and then it offers a subdued but muscular note all the way through to redline. Despite my backing off and selecting a lower gear using the shift paddles, the engine was practically inaudible. In fact, there was very little road noise or driveline noise of any kind.

Coupled to the turbo eight is a seven-speed automatic transmission that did produce the occasional miss-step, on up shifts. Usually it was fine and proved responsive to driver input from the shift paddles.

Even though the S 500 L is a large car, it's far from intimidating to drive – other than those occasions backing it down an overgrown, badly-planned driveway built in an era of much narrower cars. The parking sensors do go nuts on those occasions, but cameras scanning a 360-degree field around the car alleviate any anxiety that panels might be damaged.

That set-up is just one example of the S 500's driver-assist technology. Magic Body Control is another and features a camera to spot bumps and undulations that might upset the suspension – and adjusts spring and damper settings accordingly. That's another reason the ride comfort of the S-Class is so relentlessly acquiescent. Then there's the Active Lane Keeping Assist system, which keeps the car on the correct side of the road by braking the wheels on one side.

At times, the Mercedes would emit a high-pitched piping alarm if it detected an obstacle in front, in danger of being collected. It's distracting and unsettling – and on more than one occasion it was not clear what had prompted the system to activate.

While the passive dynamics of the S 500 L were generally impressive, even at its optimal best the Mercedes won't hold a candle for roadholding to the Porsche Panamera GTS we've reviewed in the past. But we're talking two different cars, appealing to markedly different buyer types.

While the S 500 will trail the Panamera through the bends, its dynamic prowess is still an eye-opener. Set the Airmatic suspension to 'Dynamic' and the Mercedes would nose into a turn eagerly, keeping you properly informed of what's happening through the wheel. Handling is very tidy and the S 500 can be pushed along pretty hard, point to point.

In Comfort mode it's a lot cushier and the steering is much lighter and less tactile. It will absorb every bump in the road without a hint of wallow, but there's a bit more body roll. Personally, I wouldn't bother with Comfort mode. The S 500 L's ride quality is exemplary even with Airmatic suspension set to Dynamic.

At night, the excellent LED headlights with Adaptive Highbeam Assist Plus provided exceptional illumination of the road ahead, never blinding on-coming drivers.

The late union boss, John Halfpenny, once said that when the revolution comes, everyone will drive a Mercedes-Benz. With cars like the A-Class, Benz seems unwilling to wait for the revolution, but it's plain to see with cars like the S 500 L that the prestige brand hasn't forgotten its core customer base – captains of industry and A-list celebrities.

2015 Mercedes-Benz S 500 L pricing and specifications:
Price: $312,310 (as tested, plus on-road costs)
Engine: 4.7-litre V8 turbo-petrol
Output: 335kW/700Nm
Transmission: Seven-speed automatic
Fuel: 9.2L/100km (ADR Combined)
CO2: 215g/km (ADR Combined)
Safety Rating: N/A