CARLTON, Senator, Omega - Vauxhall has made some vastly underrated big cars in the past 30 years.

There’s a reason why the Senator and the Omega were the big saloons of choice for dozens of police forces during the 1980s and 1990s - they were tough as a pair of hobnail boots.

To that list of fame you can add the Insignia.

Model-for-model the Insignia is the finest big saloon Vauxhall has ever made. It’s certainly the best-looking. Those classic curves have barely aged a day since the first Insignia rolled off the production line in 2008 and its combination of space and pace is as real-world relevant today as it was seven years ago.

But the car industry doesn’t stand still.

The Northern Echo:

The Insignia may have fewer rivals to contend with than its Vectra and Cavalier predecessors but Ford and VW have both unleashed new versions of the Mondeo and Passat in recent days.

To keep up, the Insignia has undergone significant mechanical upgrades for 2015 along with hefty price cuts (the range now starts at £16,279, nearly £2,000 less than its outgoing predecessor).

ON THE ROAD: ​ As befits a model that has dominated the mid-sized sector since its launch, the Insignia is available with a wide range of engines.

New for this year are a 140PS 2.0 CDTi diesel that somehow sneaks beneath the 100g/km CO2 limit, a 1.6 petrol turbo that’s good for 170PS and a new 2.0-litre turbo with a 250PS punch.

Good as the petrols are, it’s the diesels that make most sense for hard-up Brits.

The 2.0 DCTi ecoFLEX is available in three flavours - 120PS, 140PS and 163PS - depending on your requirements: low running costs or high performance.

Not that there’s anything weedy about the performance of the 140PS diesel. Thanks to a hefty torque output of 350Nm it’s perfectly at home in fast flowing traffic.

It’s still not the quietest diesel you’ll ever hear - despite Vauxhall going to considerable effort to check the clatter a couple of years ago - but soon settles down to a distant grumble when you’re ploughing along the A1 at 70mph.

Improvements to the dampers, roll-bars and steering have resulted in improved cabin isolation and greater comfort.

The Insignia has always been an outstanding long distance driver - now it’s better than ever thanks to an aerodynamic shutter in the lower front grille on 120/140PS versions - and the parsimonious diesel has a theoretical range to empty of more than 700 miles.

​ ON THE INSIDE: ​ The cabin layout is sensible, easy to use and very comfortable. I liked the classy instrument pack which places the speedo upfront and central with the rev counter to the left and the fuel and temperature gauges to the right. Finding a comfortable driving position is simple thanks to a seat and steering wheel with a wide range of adjustment.

And, although the Insignia’s sloping roofline robs the interior of some rear headroom, there’s enough space for five adults to sit in comfort.

​ WHAT DO YOU GET: ​ Vauxhall is particularly proud of its ‘new generation’ touch-screen infotainment interface with most functions being controlled via the screen or a computer mouse-style touchpad just behind the gearshift. It’s possible to access the core functions - radio, smartphone connection and sat nav - from the home screen by using your finger, the touchpad or voice control.

Sadly, the user interface is unnecessarily complex and I grew frustrated by the oversensitivity of the touchpad to my pinch and swipe finger gestures.

Thankfully Vauxhall’s designers have played safe and included a smattering of old-fashioned buttons for duffers like me who think touch-screens have no place in a car.

The system does have some useful features, however, like the ability to store a remarkable 60 radio stations (I didn’t know there were 60 stations broadcasting to the North-East) and synchronisation with a smartphone is seamless.

HOW PRACTICAL IS IT? ​ As well as being better looking, the Insignia hatchback is more practical than its saloon sibling. The boot has an extra 30 litres with the seats up (530 litres) and a massive 400 litres when they are folded down (1,470 litres).

There’s lots of practical storage in the cabin but the handy rear seat armrest has been quietly deleted, presumably to save a few quid.

​ RUNNING COSTS: ​ Hats off to Vauxhall for building a pokey 2.0 CDTi diesel that has CO2 emissions low enough to qualify for a zero road tax rating. The active shutter grille and low rolling resistance tyres help stretch a gallon almost 60 miles in day-to-day driving. No wonder you see so many Insignias cruising the motorway.

Even the top performing twin-turbo diesels can reach 60mpg (if you drive like a vicar) while putting out just 125g/km of CO2.

​ VERDICT: ​ The Insignia is the kind of sensible motor that grows on you. The more I drove this big rakish family car the more I came to appreciate its abilities. It isn’t outstanding in any one area but it is certainly more than the sum of its parts. If you have a growing family and can’t stand the thought of buying an MPV then an Insignia diesel makes a stylish alternative.

After all, 167,000 happy UK buyers can’t all be wrong.

VAUXHALL INSIGNIA SRi 2.0 CDTi 140PS ecoFLEX Price: £21,134.

 

​ Spec:​ Engine: ​2.0-litre turbodiesel.

Power: ​140PS.

Torque: ​350NM.

Top speed: ​127mph.

0-62mph: ​10.5 seconds.

Fuel economy: ​76.3mpg (official combined figure).

CO2 emissions: ​98g/km.

Equipment: ​ ​Electric windows, climate control, heated seats and mirrors, alloy wheels with low profile tyres, DAB radio tuner, 8-inch high resolution touch-screen, 3-D satellite navigation.

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