Twin test: Mercedes-Benz CLS vs BMW 6 Series Gran Coupe

  • You don't always have to sacrifice style with saloons
  • Driving, practicality and costs all explored
  • Find out which offer the best compromise in style and practicality

With sleeker looks, a stylish interior and a more enjoyable drive, these four-door coupes provide a more desirable alternative to the traditional sedate saloons they’re sold beside. The Mercedes-Benz CLS might have set the trend, but is it the best?

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Mercedes-Benz CLS-Class 350 CDi (2011-) vs BMW 6 Series Gran Coupe 640d (2012-)


Mercedes-Benz CLS-Class: With plenty of pulling power, this six-cylinder 3.0-litre diesel engine has more than enough oomph to overtake slower traffic. It is also wonderfully refined and effortlessly munches away motorway miles. This won’t be a car for driving enthusiasts thanks to the over-assisted steering, but select Sport mode and there is little body roll in the corners.

BMW 6 Series Gran Coupe: The diesel in this BMW makes the 640d both quicker and more economical than the CLS. It’s not ridiculously fast, but it’s a hugely impressive grand tourer thanks to a smooth eight-speed gearbox and comfortable ride. You can also alter the throttle response and speed of the gearchanges to suit the mood.



Mercedes-Benz CLS-Class: Unlike a typical two-door coupe, the CLS can seat four adults and the 520 litres of load space is more than enough for at least two sets of golf clubs. As with the previous generation there is no middle seat – this space is taken by a central console. But at least there are plenty of good-sized cubbies for those lucky enough to sit in the back.

BMW 6 Series Gran Coupe: The interior is designed to seat four adults in comfort, thanks to a longer wheelbase to that of the regular 6 Series Coupe. Boot space is smaller with the rear seats up, but unlike the CLS, there is at least a third ‘auxiliary’ seat in the rear for an adult to squeeze into for short journeys. Those with Comfort seats can be heated too.



Mercedes-Benz CLS-Class: Owners have been impressed reaching above 40mpg, but this still trails behind the BMW. The CLS will also sit in a more expensive road tax bracket thanks to higher CO2 emissions, but insurance should be cheaper. If you do choose to have your CLS maintained at a pricey Mercedes dealership, however, you should expect excellent customer service.

BMW 6 Series Gran Coupe: The BMW is more fuel effcient than the Mercedes, while lower CO2 emissions means the Gran Coupe sits in VED band F, rather than G with the CLS. It is worth noting the insurance group is higher and in order to achieve a similar age and spec to the Mercedes-Benz CLS, the 640d does on average cost ten percent more to buy in the first place.






BMW 6 Series

Gran Coupe








Fuel capacity

80 litres

70 litres

Road Tax

Band G –


Band F –





Insurance Group




6.0 seconds

5.2 seconds

Boot space

520 litres

460 litres




CO2 emissions




And the winner is:

BMW 6 Series Gran Coupe: Both four-door coupes offer something distinctive over the typical E-Class or 5 Series equivalent, but the 640d Gran Coupe wins. It may be late to the game but the higher performance, better dynamics and the option to at least consider a fifth passenger edges it ahead of the Mercedes-Benz CLS.

Mercedes-Benz CLS-Class: That’s not to say you’ll be losing out with a CLS. What made the original so appealing remains, and for those who prefer the look of the Mercedes, the CLS still provides a decent drive. The cabin is modern and the larger boot may arguably be more useful than the occasional need to accommodate a fifth passenger.


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