Citroën C6 saloon

It was originally conceived in 2006, but the Citroen C6 still stands out on the road due to its distinctive design and overall size. It's nearly five metres long, so the C6 has a large cabin with plenty of legroom in the rear. However, headroom is slightly limited, thanks to the sloping shape of the roof. Cream leather, wood inserts and large areas of glass create a luxury feel, but some of the switchgear is recognisable from lesser Citroens, such as the C5 and C4, which is unexpected on a car costing nearly £40,000. A single engine is available: a smooth and quiet 3.0-litre diesel. The suspension is very smooth on most surfaces, but from behind the wheel the flagship Citroen disappoints. Lifeless steering and body movement reminiscent of a boat means the C6 corners best at a leisurely pace. Compared to the BMW 5 Series, Jaguar XF and Mercedes E-Class, it's no surprise Citroen have sold so few.

Despite high insurance premiums and the large initial outlay, the Citroen C6 has relatively low running costs. The V6 diesel returns 38mpg, while emissions of 190g/km means it costs £245 a year to tax. Add the optional 3-year scheduled servicing contract, and the C6 will cost only £449 to maintain over the first three years, excluding tyres.

The 3.0-litre twin-turbo V6 is powerful, with a 0-62mph time of 8.9 seconds. The Citroen C6 doesn't feel that fast, but it has plenty of low-down torque to allow comfortable overtaking at motorway speeds. The air suspension ensures roadholding is impressive for a car of this size, but the body pitches and rolls in corners and the light steering leaves the driver guessing as to how much grip there is. As a result the C6 is far less invloving to drive than a Jaguar XF, for example.

Open the rear doors of the C6, and you are presented with a beautifully crafted cabin with soft touch materials and sumptuous cream leather. All the seats are very comfortable and rear legroom is vast. Noise levels are very low and the head-up display projects the car's vital information on the windscreen, so drivers dont have to take their eyes off the road. The sloping roof does restrict headroom in the rear slightly, but overall, most people will enjoy spending time inside Citroen's top-of-the-range saloon.

The large 72-litre fuel tank and efficient diesel engine mean the C6 can travel up to 570 miles between fill-ups - and covering large distances is where the C6 excels. Large oval doorbins can swallow water bottles and newspapers with ease, but overall there is a lack of useful storage in the cabin. The centre console is borrowed from the old Peugeot 407, and as a result some of the switches and buttons are very fiddly to use. Parking sensors must be relied upon when parking due to the long overhangs at the front and rear.

Citroen has an ever-improving reliability record, and the smooth diesel engine, which was jointly developed with Ford, is unlikely to cause any major problems. The numerous electric gadgets are far more likely to develop a reason to visit your dealer. The cabin feels well screwed together and if looked after should last for some time. The five-star Euro NCAP crash test rating provides total peace of mind in the event of an accident.

The Citroen C6 is very well equipped - it has heated leather seats front and rear, cruise control, dual-zone air conditioning, sat-nav, a lane changing warning system, tyre pressure monitors, a head-up-display and a spoiler that extends at higher speeds. But none of this clever technology can detract from the asking price of the Citroen C6 when comapred to the BMW 5 Series or Audi A6. The flagship Citroen will also depreciate faster than its rivals, retaining just over 30 per cent of its list price after three years.