A STRETCH of 16 years hasn't diminished the magnetic appeal of Audi's original full-blown SUV, the Q7.

Not only has the big seven-seater got cleaner, greener and more efficient, it has also become a technical tour de force.

Up there with the best of them is the Q7 55 TFSI e quattro PHEV model, which as a plug-in hybrid combines a 3.0-litre V6 petrol engine with a powerful electric motor.

The result is a system output of a hefty 381PS and 600Nm of torque plus an official electric-only range of 29 miles, though our own return was actually 23.6 miles.

Nonetheless it's just about enough to manage a local commute with zero emissions, while the efficiency of the PHEV offers a Combined 108 miles per gallon plus low CO2 emissions of 60g/km.

Our model was the Black Edition, third in line of the four available Q7 trim grades, and benefited from the extra passenger space afforded by having five seats rather than seven.

Classy, comfortable and high tech throughout, there was plenty of black on show as the name would suggest, but not so much as to totally dominate the car's cabin or exterior.

So there's piano black in the dash area and inserts around it, black suede in the door linings and black Valcona leather for the seats - which are soft, supple and beautifully crafted.

Rear space is vast and that includes the centre rear seating position, despite the presence of a wide carpeted transmission tunnel and if the middle seat isn't in use you can pull down the centre armrest with its pair of flip-up cup holders.

The boot is also very accommodating, though some space is taken up by the PHEV charging cables.

Out on the road the Q7 is a pretty big brute with its dimensions of five metres in length, width of almost two metres and 1.5-metre height, but it performs like a vehicle far smaller - feeling stable and agile regardless of road conditions.

At the same time the likes of quattro all-wheel drive, adaptive air suspension and electromechanical power steering makes for a degree of off-road assurance too.

Drive modes of Comfort, Efficiency, Allroad, Offroad, Individual, Dynamic and Auto ensure there's a setting to suit every mood or type of terrain.

There's no end of tech in this car - from handy features like a mobile phone charging pad - and if you opt for Black Edition there's a bright and airy ambience courtesy of an enormous sliding glass sunroof.

And using the infotainment system with MMI Navigation Plus and MMI Touch you can access Audi Connect digital services while the 12.3-inch virtual cockpit gives an overview of hybrid info like battery charge status and electric range.