The quickest TT is powered by a 2.5-litre TFSI engine, a unit that's unique to this model. It's a turbocharged five-cylinder engine that has a distinctive sound and feel, especially under hard acceleration. With 340bhp it always feels incredibly punchy and eager, with 0-62mph taking just 4.6 seconds in the coupe version. Crucially, that's faster than other two-seater sports cars like the Porsche Cayman S and even the more powerful Mercedes-Benz SLK55 AMG.
The Roadster is barely any slower with a 0-62mph time of 4.7 seconds while both have a limited top speed of 155mph. All cars come with a great six-speed manual gearbox which has slick and short shifts, adding to the high performance feel. But despite these impressive figures, the TT RS is a very easy car to drive at sedate speeds and even stop start traffic doesn't pose a problem thanks to a light clutch pedal.
When you do want to go quicker, the RS will deliver its power smoothly and predictably, with no turbo lag at all.
As you'd expect of a high performance Audi, the TT RS is fitted with the quattro four-wheel drive system as standard. This gives great reassurance, especially in wet conditions and means there's excellent traction out of slow corners too, ideal for driving quickly yet smoothly. The steering is a little disappointing though. True, it's well weighted, but it doesn't feel as involving as other sports cars like the Porsche Cayman.
However, that's not to say that the TT RS isn't very agile, helped by the use of lightweight aluminium in the body and lowered sports suspension. It turns in precisely and deals with quick changes of direction well with virtually no body roll. An optional magnetic ride system is available, which allows the driver to change the suspension settings. It includes a sport mode that tightens the ride even further for demanding roads.
All cars get a Sport button (on the centre console) which increases throttle response and gives the exhaust an even louder note.
There are a few features that make the RS stand out from the standard TT, but it's not particularly distinctive for what should be the most extreme model in the range. The neat instrument dials, sports seats and chunky steering wheel are the main differences, but while the seats are very supportive, the chunky steering wheel is almost too thick and not that enjoyable to hold.
Quality is excellent though and the finish is unsurpassed with a precise feel to all the switches and controls. The cabin is snug, but offers enough leg and head room for most. Visibility is good too, although the view out of the back is somewhat limited, especially in the roadster version when the roof is up.
The standard TT has a fairly firm ride and the RS comes with even stiffer suspension. As a result, it struggles to deal with rough or potholed roads and can feel very fidgety, however the optional magnetic ride includes a softer setting for comfort, which improves things somewhat. Aside from the enjoyable engine and exhaust sound, noise is kept to a minimum.
The roadster is especially impressive considering it uses a fabric roof. It's refined with it up, yet drop it down and it's comfortable even in colder weather thanks to a snug cabin and heated seats as standard. Other convertibles are quieter at motorway speeds though.