AUDI is wasting no time expanding its new A4 line up with the launch of an estate that's as much a blockbuster as the saloon.

The new A4 Avant is the biggest load lugger in its class and comes with a range of fuel efficient engines that set new standards.

It's priced from £27,300 - £1,400 more than the saloon which is coming on stream in the next few weeks - and will be on the road early next year.

As with the saloon the Avant is a trailblazer for new technology and can be fitted with an array of systems including Audi's virtual cockpit and devices which enable it almost to drive itself through traffic.

Visually, and as with the four previous generations of the A4, the car makes the transition from saloon to estate with ease and it is good looking and sleek.

Never forget that this is the body style Audi prefers for its high performance RS 4 models and aerodynamically the new Avant is very slippery.

When it comes to luggage capacity the latest Avant musters 505 litres of space which is more than that of its key competitors in the form of the BMW 3 Series Touring or the Mercedes C-Class estate.

The tailgate of the A4 is power operated and can be opened and closed hands-free by waggling your foot under the rear bumper while the luggage blind slides back and forward automatically.

The loadbed is a metre wide and with the rear seats folded flat capacity increases to 1,510 litres which is on par with the others.

From a practical perspective the loading lip is relatively low at 63cm and includes a protective strip across the top of the bumper.

Below the boot floor is not only a spare wheel but also a selection of straps, nets and telescopic partitions for securing cargo.

Rear visibility for the driver is marginally better than in the saloon yet even so the Avant can be fitted with automatic parking aids as well as cameras all round.

The towing limit is 2.1 tonnes with the car itself weighing between 1.5 and 1.7 tonnes depending on engine and specification.

Audi's emphasis on reducing drag with the design of the Avant has not only helped make it economical but also made it very quiet inside.

On the road it feels just as accomplished as its four-door sibling and can be had in all-wheel-drive quattro set up which is available on mid-range Sport models and the top specification S line cars.

The quattro line up comprises a two-litre petrol, a two-litre diesel and two versions of Audi's powerful three-litre V6 diesel, one of which being the most fuel efficient six cylinder engine in the world.

It develops 218ps and is mated to a seven-speed S tronic semi-automatic transmission which makes it well refined.

Plenty of power is on tap throughout the rev range and although it has not got the same amount of kick as the bigger 272ps V6 diesel which is fitted in the range topping quattro automatic it is almost 10 per cent more economical at 61.4mpg.

In Sport trim this version of the Avant costs from £37,080 and with emissions of 119g/km it falls into the 21 per cent tax bracket for business drivers - quite amazing for a three-litre model.

With a two-litre diesel engine the Avant is even more appealing on the taxation front and with the 150ps ultra diesel under the bonnet it is rated at 70.6mpg which equates to 104g/km and 18 per cent tax.

We tried both engines and the ultra, albeit with a six-speed manual box, recorded an average of 45 to the gallon which is more than acceptable in an estate priced from £30,550.

The three-litre quattro costs from £37,080 and not surprisingly was sportier to drive yet even so managed 41mpg over a similar route.

The Avant range tops out at £40,350 for the high powered diesel quattro in S line trim yet extras - and there are plenty to be had including a head up display, the LCD virtual instrument panel and a wireless phone charger - can push the price beyond the £50,000 mark.

Nevertheless this is a car with a premium persona and among estates that is a commodity which makes the A4 Avant very appealing.