You buy an Audi TT RS for its engine. If you merely wanted a very quick Audi TT, the TTS model with its 2.0-litre four-cylinder turbo engine more than fits the bill. It's good for 272PS and delivers its power effectively in almost all weathers. The RS is an altogether more charismatic thing, the warbling of its in-line 2.5-litre five-cylinder engine harking back to more famous Quattros of the past. In RS plus guise, that engine has been massaged from 340 to a full 360PS which, in coupe form and with the optional S tronic twin-clutch transmission fitted, will catapult you from rest to 62mph in just 4.1 seconds (six-speed manual version 4.3 seconds). The Roadster is only a tenth of a second slower and whether you choose soft top or metal roof, the top speed is electronically limited to a distinctly liberal 174mph.
As well as the additional power, the RS plus gets a sportier exhaust system. Don't think that the five-pot engine is a hefty old lump either. It achieves excellent economy figures and weighs just 183kg which contributes to a kerb weight for the manual Coupe of just 1450kg. The TT's Audi Space Frame chassis blends lightweight aluminium with steel where it's required for strength and this relatively light weight helps deliver excellent acceleration and agility. Peak torque is rated at 465Nm and it's deployed to the road through Audi's quattro all-wheel drive transmission.
Whether you choose Coupe or Roadster, you get the same 19-inch five-arm "Rotor" design titanium-look alloy wheels which replace the 18-inch five double spoke examples fitted to the standard TT RS.
The Audi TT RS plus is one of those cars that is easy to dismiss. The lazy view is that it's not as good as the latest Porsche Boxster or Cayman, relies on a dated five-cylinder turbo engine and is ferociously thirsty.
The RS plus doesn't change the formula too radically from the existing TT RS. There's just a little more power and a bit more equipment on offer. The pricing has been kept sensible in relation to its rivals, even if the thought of a £50k+ Audi TT can be difficult for some to countenance. Capability counts here, and the RS plus is a hugely satisfying ownership proposition. Day in, day out, this one is extremely hard to beat.