It’s been a few hours now since we handed back the keys to the Mercedes, and to be honest it’s very impressive. However I should have expected that, as this Mercedes is the CLS 55 — it’s been reworked by Mercedes’ in-house tuner, AMG, to produce 350kW with a whopping 700Nm of torque. The factory states an impressive 0 to 100kph time of just 4.7 seconds, and recently the CLS 55 was timed by an American motoring magazine at a lightning 12.5 seconds over the quarter mile. But it’s not brute power that makes the CLS 55 an outstanding piece of machinery.

Looking from the outside your first reaction was probably something similar to my own: “Is this really a Mercedes?” In the past Mercedes has designed cars with function and purpose over form. First impressions are that this philosophy seems to have done a complete turn around as Mercedes describes the CLS as a coupe shape with the functionality of four doors, and it certainly has been tastefully done. But have the techno-mad Germans given in to style over function? Well, not exactly.

As the saying goes, beauty is only skin deep, and under the skin of the new CLS the Mercedes engineers had an absolute field day.

For starters, the paint’s clear coat has been especially developed with, wait for it, nano technology. Tiny ceramic particles — measuring one millionth of a millimetre — are mixed into the clear coat to form a surface that is said to be three times more scratch-resistant than conventional systems.

Even the long, flowing lines of the bodywork have a secret agenda. This car’s bonnet has been designed to deflect airflow past the windscreen wipers for added efficiency. Underneath, the engine, gearbox and suspension have all been covered by plastic panels to reduce lift, and improve stability. All these features help the CLS 55 to a respectable coefficient of drag figure of 0.30.

Mercedes Benz has always been admired for its innovative technology and safety. The body construction of the new CLS is no exception; in fact it’s just what you would expect from Mercedes. Front and rear crash boxes are bolted on to cut repair times down. The A, B and C-pillars are all triple-walled sheet steel. Aluminium is used for the bonnet and rear parcel tray.

For front passenger safety, seat belts and airbags are controlled by an electronic unit which has two sensors located in the front cross member. In a frontal impact the unit can calculate the severity of the crash and decide at what force to deploy the airbags and seat belt tensioners. Approach the car and you don’t need to use the key, as this CLS has the ‘Keyless Go’ option. As you come into range, the car recognises the encoded key and you need to do is touch the handle, and it’s open.

Inside the two front nappa and alcantara leather seats fit just nicely, and as you would expect they are virtually adjustable any which way you like. In the rear there are just two individual seats, with a surprising amount of legroom, which underlines that this is a true sedan, and not a just coupe with extra doors. Leather spills out over the dashboard and across the doors, with inserts of matt-finished walnut wood. If you are not a fan of the old-school walnut, then a black bird’s-eye maple wood is also available.

As for the rest of the interior, it’s all first class travelling. Included are as many airbags as you can count, and there’s also the air conditioning system that Mercedes calls Thermotronic. It’s a four-zone climate control system which allows each occupant to choose their desired climate, with individual controls and displays for each seat. The system not only measures inside and outside temperatures, but also compensates for sunlight shining into the car.

When it comes to starting, the CLS its dead easy. With the Keyless Go option you can leave the keys safely in your pocket. All that’s required is to press the button on the top of the shift lever, and eight of Mercedes Benz’s finest come to life. Under the bonnet AMG has installed its familiar 5.4-litre, V8 single overhead cam three-valve engine, with the addition of a belt-driven Lysholm screw-type supercharger. It’s the same engine used in the AMG SL 55 roadster and E 55 sedan. To keep inlet temperatures down as much as possible, between the cylinder banks sits an intercooler that operates as an air to water heat exchanger, extracting heat from the compressed air and transferring it to the coolant. Separate from the main cooling system, it pumps fluid through a cooler situated between the air conditioning condenser and radiator.

On top of the exposed supercharger you’ll find a plate with the name of the technician responsible for building the engine. This is part of AMG’s one-man-one engine-policy, with everything personally checked to the last bolt. Thanks to AMG for leaving the engine exposed, and not hiding it all under a plastic cover.

Another feature of the supercharger is the installation of an electromagnetic clutch controlled by the ECU. Depending on throttle position, load and speed the ECU can disengage and engage the supercharger.

There’s only one gearbox option, and it’s the reliable Mercedes five-speed automatic with AMG Speedshift. In full auto mode it uses a Mercedes development it calls active braking downshift technology, which helps to select the right gear when exiting corners. If you feel like taking control you can shift straight to the Speedshift mode, which can be operated in two ways — either by toggling the shift lever side to side, or by using buttons located on the steering wheel. What’s more important is that you effectively have a sequential manual gearbox with no auto shift, leaving you in complete control of the gear selection.

Trundling around suburban streets the CLS 55 behaves just like any other Mercedes does, which is a nice surprise. With 350kW and 700Nm at 2650rpm you would expect this beast to be hard to tame, but instead it’s rather civilized. For a car with 19-inch wheels covered in 30-profile rear, 35-profile front tyres you would expect a ride more on the crash and bang side. But instead the CLS soaks up the bumps quite well, and delivers a ride that’s easy to live with. This is mostly due to the Mercedes Airmatic DC system. DC for Dual Control, which is basically a description of the springing and damping. Air bellows replace the steel springs and are able to offer variable pressure individually to compensate for uneven road surfaces. When the system senses the car is at speed and a stiffer set-up is required, it simply locks the air volume in the bellows to restrict compression. Dampers are controlled by the Adaptive Damping System (ADS) that is linked to the Airmatic DC. Sensors placed around the car determine what settings are needed depending on loads, and report back to the Airmatic DC. Calculations can be carried out in 0.05 of a second.

Accessing the open road lets you hit your foot to the floor, and suddenly the world changes in the blink of an eye. Instantly the CLS 55 breaks out of cruiser mode and jumps straight to ballistic. Like one of the Three Tenors it opens up its lungs, and has a voice you could just listen to all day. As you would expect, the torque from the supercharger just keeps pouring it on with what seems like endless amounts of power.

If you are worried about taming this beast, don’t be. Mercedes has installed eight-piston brake callipers with dinner plate-sized 360mm discs up front and four-piston callipers with 330mm discs at the rear. It’s all controlled by the brake by a wire system called Sensotronic brake control. Another feature of the braking system is that it can be used by the ESP (electronic stability program) to brake inside wheels on corners without reducing speed, to give the effect of a limited slip differential.

Unfortunately our time with the CLS 55 was limited to just a few precious hours. But it didn’t take long for us to realise this is one of the most complete super saloons you can buy today. The power is there when it’s needed, and the technological innovations work quietly by themselves to keep you on the tarmac and moving forward. That’s what’s so impressive about the CLS 55, all you have to do is enjoy the drive and the car will look after the rest.