KEY POINTS:
Supercars are supposed to break new ground and question perceptions about what is possible from a road-registered production car.
Audi's new performance flagship, the RS6 Avant, does just that. It's a top-tier supercar, capable of 0-100km/h in 4.6 seconds - as fast as the company's mid-engined R8 - and 0-200km/h in little more than 14 seconds, yet it's also a roomy station wagon with seating for five adults.
The new twin-turbo V10 engine under the bonnet pumps out 426kW/650Nm, making the RS6 Audi's most-powerful model and easily the most-potent wagon on the market.
The "standard" S6 - if you can call it such a thing - hardly compares, with a mere 320kW/540Nm from its 5.2-litre engine.
Here's another perception challenged - rarity. By their nature, supercars are exclusive, but such is the expected demand of the RS6 in New Zealand, importer European Motor Distributors (EMD) expects it to account for one-third of total A6 sales.
That's partly a measure of the small size of the Kiwi market - EMD expects an allocation of just 40 RS6s in the first year - but it's still an impressive statistic.
It seems New Zealanders are already developing a huge appetite for this wagon with massive performance, even at an expected price of $251,000.
For the high price and surreal acceleration, the RS6 looks painfully low key.
The large front intakes and the delicately flared wheelarches - their squared-off shape is a styling homage to the original Audi Quattro of the 1980s - are the most obvious visual changes over the standard A6 Avant. The car squats low to the ground and will wear 20-inch alloys in New Zealand specification.
The 5.0-litre V10 is based on the 5.2-litre unit used in the S6 and S8 models, but Audi says almost every component has been modified. The two turbos - equal size, one on each bank of cylinders - help produce maximum torque at a diesel-like 1500rpm. A very high compression ratio helps the rorty V10 register 14.0 litres per 100km in European Combined fuel economy tests.
But don't expect to achieve that figure often if you've any inclination to enjoy the RS6. On a short open-road test route in the south of France during Audi's media launch for the car, we registered 23.0 litres per 100km despite a fair bit of traffic and only occasional deployment of maximum thrust.
Still, supercars and fuel economy - the two don't go together at all. On the road, the RS6 is staggeringly fast, the newly developed six-speed Tiptronic automatic trans-mission slamming from cog to cog under load (shift times have been halved compared with the standard A6). The throbbing noise of the V10 is muted inside the cabin, but you can't escape the g-forces or visual sensations of scarily blurred scenery.
In some respects, the RS6 is old-school Audi.
It doesn't pick up the new platform architecture and steering systems of the A5/S5 coupe and latest A4, so it's still a car with the engine mounted a long way forward and it lacks that last level of involvement you might expect from a super-coupe - such as the RS5 rumoured to be in development.
You would never call it aloof - there's too much velocity and chassis engineering involved for the driver to be anything other than engrossed in the experience - but on public roads you are still keenly aware of the car's size and two-tonne-plus weight.
The RS6 features adaptive damping, Audi's latest quattro four-wheel-drive system with a 60 per cent bias to the rear, and Dynamic Ride Control, which links the suspension of individual wheels diagonally to eliminate pitch and roll on bumpy corners.
The steering has a slightly artificial feel, but it's still super-quick with just 2.2 turns lock-to-lock.
But any doubts about the RS6's ultimate abilities were dispatched during four precious laps of the famous Paul Ricard racing circuit.
Its relentless performance, supreme stability and rock-solid chassis make it a very rare thing: a road car that excels on the racetrack.
The RS6 is not a dynamic masterpiece like the landmark RS4 - which is now discontinued, in line with Audi's philosophy of producing only one RS-badged model at a time.
The RS6 is larger, heavier and much less communicative.
But it's also an astonishing piece of engineering and an outrageously fast machine in all weathers.
With barely imaginable acceleration, surreal levels of traction and the sheer shock value of a full-size estate with supercar performance, you can forgive the loss of a little finesse.
The RS6 Avant is a superstar in the already rarefied world of fast wagons.
