Ray Hutton

Vauxhall isn’t known for taking risks. It does plain cars well but they lack the spark of some competitors and can’t attract those determined to have something from a premium brand. In the future, it has determined, this will change: 40% of Vauxhalls will be out-of-the-ordinary niche models, offering something truly different. Signum is among the first of these.

Actually, Signum is a version of the Vectra, but not badged as such. Its wheelbase is 5in longer than that of the Vectra, though the car is only 1½in longer overall. It is halfway between a hatchback and an estate. Buyers are not supposed to like posh five-door cars but Vauxhall reckons to offer something practical and luxurious with a style that is unusual.

The extra space between the wheels is all in the rear compartment. And here is the surprise: instead of being arranged with three seats Signum provides comfort and convenience for two.

The rear seats are like front ones, sliding back and forth and reclining. There is a narrow perch between them, with seatbelt, but nobody will want to sit there. Turn that over and it becomes an armrest plus storage area. For £200 extra (standard on the top model) a “travel assistant” plugs into this space, including a cool box, tray tables and a power point. There are also small storage boxes in the roof console. Otherwise, Signum is much like a Vectra.

The two rear-seat passengers do get a good deal, although the legroom is matched by some conventional saloons. The riding and driving neither gains nor loses from the longer wheelbase, which means it is a good average for the class.

Three petrol and three diesel engines are offered. Of those that I tried, the most impressive was the3 litre V6 diesel Signum CDTi (from £23,995), which is punchy, quiet and should be well suited to the five-speed auto transmission; it has a new six-speed gearbox as standard.

With business users in mind, there is a 2.2 litre 153bhp new injection petrol engine called Direct. It is adequately refined but the Signum is nicer to drive with more power — from the 177bhp V6 diesel, the 175bhp 2 litre turbo petrol engine or the 211bhp 3.2 litre petrol V6.

Prices start at £17,995, roughly £1,300 more than an equivalent Vectra. Aside from the businessman who wants to snooze or work on a laptop in the back, it isn’t clear who will want the Signum. Vauxhall talks vaguely of those considering Alfa Romeo or Volvo, but doesn’t really seem to know who will buy it.

I suppose that’s what happens when you take a risk and do something completely different.