We say The answer to the question of what an S-Class Coupe would look lie, the CL is superb car but it is also superbly expensive.Performance The engine choice includes a 5-litre V6, 6-litre V12 or AMG version and all are massively powerful. The engineering that has gone in to the CL is evident in its extraordinary performance.Emissions CO2 figures, the criteria for road tax, are astronomical at a little under 300g/km. Don’t expect any more than 20mpg with eco-driving and CL owners are unlikely to even attempt to.Driving The Mercedes CL is smooth and glides around corners. A lot of effort has been put into making it enjoyable and Mercedes has come up trumps.Feel Despite the performance stats the CL Coupe is as quite as a car can possibly be and even the V12 is a murmur from inside the car.Space The CL comes with good space for 2+2 and back passengers have adequate leg room. Coupe roof limits head room at the back but the boot is decent.Equipment Climate and cruise control, CD changer, alloys, sat nav, leather... the list is impressive.Price The top model comes in a shade under £150K and this is matched by huge running costs.Quality 30-year breakdown cover (which can be retained after the fifth year) indicates what Mercedes think of the build quality, but the interior is a little cheap for the price you will be paying.Safety All the kit you'd expect on a car like this including airbags and stability control. Not tested in EuroNCAP – few expensive cars are – but would probably have done well.Pros The Mercedes CL Coupe is luxurious and fast, the two things demanded from a sporty coupe. Well-built and with a good, smooth ride, it is an excellent car.Cons The price is astronomical and it has running costs to match.Alternatives Bentley Continental GT, Aston Martin DB9