Under the bonnet of the TT RS Roadster is a lightened, by 26kg, retuned 2.5-litre four-cylinder petrol engine that produces 394bhp. That’s enough to provide the range-topping TT with a 0-62mph time quick enough to make R8 drivers peer nervously in their rear view mirrors. Peak torque, a generous 354lbft, is available from as little as 1,700rpm.

Unfortunately, despite the reduction in mass up front, the TT RS remains nose heavy, with a far from ideal 60:40 weight distribution.

The Haldex four-wheel drive system can alter the torque split based on which drive mode has been selected, sending up to 100 per cent of the power to the rear wheels if necessary, while torque vectoring by braking allows for even finer adjustments on a wheel to wheel basis.

The RS sits 10mm lower than the standard TT whether you stick with the MacPherson struts up front and rear multi-link or splash out on the adaptive dampers as part of the Dynamic Package. The spring rates, bushes, stability control and steering have all been tuned

The RS isn’t subtle about letting the world know that it’s a little bit special. Perhaps the first things you’ll notice are the fixed spoiler and huge oval tail pipes that flank the large rear diffuser. Air intakes are larger, as are the side sills, and the honeycomb lattice grille is new.

The interior is dark, sombre even, but if you can live with that – and you can, trust me – then you’ll enjoy what is a very, very classy cabin.

The layout is beautifully simple – the climate controls are housed within the three central air vents, the heated seats within the two outermost – and the fit and finish impeccable.

There’s no screen in the centre of the dashboard and there are no analogue dials in the instrument binnacle. What you get instead is Audi’s Virtual Cockpit. It’s a full-width high resolution full colour LCD screen that displays digital gauges – that can be minimised – along with the sat nav or any other information that the driver requires.

You also get an additional screen beyond what you would see in a lesser TT that puts the rev counter and digital speedometer right in the centre of the instrument binnacle, providing you with a completely unobscured view.

Audi’s multimedia interface infotainment system, found here in MMI Navigation Plus configuration, provides access to the excellent sat nav and Audi Connect serviced with Google Maps and Street View destination input. As with other cars in the Aud stable, the familiar control dial is touch sensitive, allowing you to program the sat nav using the excellent handwriting recognition software. It’s a much more satisfactory system than using the jog wheel to select letters from an on-screen circular interface.

The Roadster, unsurprisingly, accommodates only two people. The Super Sport seats in black Alcantara are firm, supportive and very comfortable. The space that would have been occupied by the perfunctory rear seats in the Coupe is used to stow the roof without compromising the boot.

You’ll sit behind a TT RS sport leather and Alcantara steering wheel with multifunction plus with 2 satellite buttons for Engine Start/Stop and Audi Drive Select.

Performance is nothing short of sensational. It would be easy to describe the TT RS as frighteningly fast but, the truth is, it isn’t. Not frightening at least. The truth is, the way it puts down its power is sublime, so linear, so controlled that it can disguise just how rapidly speed is being accumulated.

And it is rapid. Keep your foot to the floor and 100mph will arrive in a quite frankly ridiculous 8.4 seconds. No one can accuse the TT RS of being all show and no go. In fact, given its supercar-scaring performance you could argue that it’s a tad understated.

You’ll swap ratios using Audi’s S Tronic seven-speed dual clutch automatic gearbox and it’s an absolute delight, a perfect match for the character of the engine, providing assertive, no-nonsense changes whether you’re swapping cogs manually or letting the box do its own thing.

The TT RS feels compact and agile. The electrically-assisted steering with its varying ratio – faster on lock than straight ahead – is direct and precise. Turn the wheel and the front end will follow without pause for thought. Torque is shifted to the rear long before front-end grip has dissipated and reapplying the power reigns in any tendency towards understeer. You can feel a little disconnected from proceedings at times thanks to steering that doesn't feed a hug amount of information back to the driver but it rarely slows you down.

Audi’s Drive Select lets you choose the mode to suit your mood. There’s four to choose from – Comfort, Efficiency, Dynamic and Individual – but aside from a brief foray into comfort and efficiency territory I spent most of my time in Dynamic mode.

You’ll find everything tightens up with a more willing dual-clutch gearbox, meatier steering, more responsive throttle and firmer damper settings. The exhaust note is much, much angrier too. Use the paddles on the steering column and you get a delightful bark with every upshift. It’s simply intoxicating.

The ride is firm, even in Comfort mode – why would you expect anything else – but despite that firmness the TT RS deals with smaller imperfections with aplomb. It’s only when things really start to get rough that its limitations are exposed.

None of that will matter when you’re blasting through the countryside – within legal speed limits of course – hitting every apex and putting the power down hard as you exit. It is effortless in the way that it delivers its spectacular performance. Sitting behind the wheel, feeling the car flow through a series of quick corners like liquid metal, you never feel overwhelmed by the monstrous power at your disposal. You never feel anything less than in control.

The TT RS is also a capable, and comfortable, machine that, if called upon, is perfectly able to deliver you relaxed and refreshed at your destination.

The RS is the finest version of a brilliant car, I'm in no doubt about that, but it does face some very stiff opposition, particularly from certain other German manufacturers. Opposition that, invariably, offers a slightly more involving drive, even if they can't quite match the performance.

Then there is always that question about how much power is too much. I can safely say that as far as the TT is concerned, 394bhp is just dandy. It's breadth of abilities is breathtaking. It is supercar fast – and not just in a straight line – yet comfortable enough to be your daily driver. There's even enough room in the boot to put some things.

The TT RS is not perfect – perfection is overrated anyway – but it does so much so well that it's impossible not to forgive the minor flaws that it does have.

And anyway... just look at it!

Audi TT RS Roadster

Price: £58.085

As tested: £68,490

Engine: 2.5-litre 5-cylinder turbocharged

Transmission: S tronic 7-speed dual-clutch driving all four wheels

Max power: 394bhp

Max torque: 354lbft @ 1,700rpm

Max speed (regulated): 174mph

Acceleration (0-62mph): 3.9sec

Combined: 27.9 - 30.1mpg

Emissions (C02): 183g/km

For more information visit www.audi.co.uk