The Mercedes S-Class has long been a benchmark in luxury limousines. It's designed for diplomats, royalty, and business folk with more commas in their bank balance than the Bible has psalms.
This S 350 L BlueTEC edition, the cleanest diesel S-Class to date, retails for £64,155 as standard. Our test car, however, features just about every Mercedes-Benz option going, including night vision, TV tuners and Bang & Olufsen front and rear entertainment systems, which push the price up to £94,650.
The cabin of the S350 L makes your favourite business-class airline look like a dusty old rickshaw. It's exceptionally luxurious, with just the right amount of leather, wood, massaging seats and fridges in which to stash bottles of Cristal. (There's just one fridge, stashed between the rear seats, but that's all you need, really.)
The comfort levels don't dip much once the car is in motion. The S-Class is blessed with a fancy Airmatic suspension system, which uses automatically controlled air springs which adjust dynamically depending on the driving conditions.
At higher speeds, it lowers the car's ride height to improve aerodynamic efficiency, while at lower speeds, it can raise the ride height to reduce the impact of particularly vicious speed bumps. It'll even help balance the car. If there's a heavy object -- say a particularly fat exec -- positioned on one corner of the vehicle, it'll raise that corner to make the car as level as possible, improving handling and comfort.
What's more, the car's front seats will actively support you as you corner. Swing the car to the left and supports on the right will move in to cradle you on the right. Turn to the right and the same will happen on the opposite side.
On the whole, the car handles surprisingly well for something so large, but it's not quite as rewarding a drive as the Jaguar XJ.
The vast majority of the S-Class' entertainment and information functions are accessed via the car's COMAND interface, which is controlled via a knob on the centre console. It's very similar to the ConnectedDrive unit seen in BMWs, as it must be twisted, pushed and pulled to control a menu interface that resides on a large, dash-mounted display.
The system has pros and cons. Its graphical user interface is easier to navigate than BMW's system, but it doesn't include any physical shortcut buttons to take you instantly to the sat-nav or radio, for example. As a result, you'll have to spend time navigating your way through the menu system to get to your chosen function.
The eight-inch COMAND display in this car is somewhat disappointing, too. It's fairly large in comparison to the screens in most cars, but it's outclassed by the 10.2-inch 1,280x480-pixel unit fitted in the BMW 7 series. If you're a gadget fiend, you can't help but feel Mercedes-Benz missed a trick in this area.
The COMAND display does have one very impressive trick up its sleeve, which the BMW does not -- Splitview. Splitview uses a filter over the display to direct half the display's pixels towards the passenger and the other half towards the driver, allowing them to see two different images on the same screen simultaneously. The driver, for example, can keep an eye on the directions from the sat-nav, while the passenger enjoys a spot of Freeview television, the radio interface, or whatever else they please by way of an infra-red remote control.
Bang & Olufsen stereo
Our test car came fitted with a Bang & Olufsen entertainment package, which costs a whopping £8,100. That breaks down as £6,070 for the front-seat package and another £2,030 for the rear. It sounds impressive on paper, but when we threw on some music and cranked the volume knob, we were left feeling incredibly disappointed. The system uses 15 speakers, fancy 'acoustic lens' tweeters, and is powered by a 1,200 Watt amplifier, but it proves, without a shadow of doubt, that big numbers don't always equate to good sound.
The speakers are certainly better than those you'd find in most cars, but in comparison to other luxury cars, they don't sound sound anywhere near powerful enough. The sound qualify is fine, but the audio is delivered in a very limp-wristed manner. It's definitely not on a par with the Burmester setup seen in the Porsche Panamera.
The car's Night View Assist feature is far more impressive. This system uses a set of infrared lights pointed at the road ahead and an infrared camera that feeds visuals to a screen mounted in the instrument binnacle. It works in similar fashion to the infrared cameras police use during high speed chases, and shows an enhanced image of the road ahead at night.
The system is, unfortunately, a bit of a gimmick, as it won't work unless the car's headlights are also activated. As a result, you'll see just as much looking through the windscreen as you would looking at the night vision display.
It drives itself
The S-Class's most impressive feature by far its Distronic Plus autonomous cruise control, which pretty much lets the car drive all by itself. Simply flick the stalk on the left side of the steering wheel and the car will lock onto the vehicle directly in front of it, matching it as it accelerates, cruises, slows or stops. All you have to do is steer the car and supervise the system.
As tempting as it might be to doze off, supervision is necessary, as Distronic Plus has a tendency to deactivate itself whenever it gets confused about what vehicle it's supposed to be following. If another vehicle swerves between you and the car you were following, or the car you're tracking decides to swerve out of lane suddenly (and you don't swerve with it) it'll deactivate itself and leave you to take over.
For the most part, though, it's an incredibly impressive system and is an absolute godsend in heavy traffic.
The big engine that could
The S-Class comes with a wide choice of engines. However, the latest model, our S 350 BlueTEC, is fitted with one of the cleanest diesel engines seen in a car this size. The three-litre lump outputs 164g of carbon dioxide per kilometre, which is impressive for such a large vehicle. The BMW 730d SE, for reference, outputs CO2 at a rate of 178g/km.
The S350 L BlueTEC claims to reduce other types of harmful emissions, too. It's fitted with Merc's adBlue exhaust gas cleaning system. After exhaust gases are cleaned by the catalytic convertor and diesel particulate filter, adBlue liquid is injected into the exhaust stream to produce ammonia. This ammonia breaks down the harmful nitrogen oxide into nitrogen and water vapour -- gases that occur naturally in the air. According to Mercedes, this reduces nitrogen oxide emissions by up to 80 per cent.
Despite its cleanliness, the S350 L BlueTEC engine still performs superbly. It chucks out 258hp and 620Nm of torque. That's 13hp and 80Nm more than the BMW 730d SE. It's a bit quicker, too -- achieving 0-60mph in 7.1 seconds and an electronically limited top speed of 155mph. The Beemer does the sprint in 7.2 seconds and tops out at 153mph.
The Mercedes-Benz S 350 L is a fabulous vehicle. It has impeccable road manners whether it's you or the car's Distronic feature that's doing the driving, and is incredibly comfortable. Its Bang & Olufsen audio system is a bit rubbish given its ludicrous price tag, but if you're after a luxury saloon, we couldn't recommend this car highly enough.