FOR an Audi to wear the coveted RS badge it has to be at the pinnacle of performance.

The current RS line up is a heady collection which includes some of the greatest cars of our time.

Now there's a new member of this exclusive club and it's an SUV - an unlikely genre for a high performance model.

The RS Q3 is a compact 4x4 with attitude and it has some serious firepower under the bonnet.

Fitted with the same five cylinder, 2-5-litre engine as Audi uses in the sleek TT RS it develops 310ps which produces some startling figures for a car that tips the scales at almost 1.7 tonnes.

It also produces a delightful sound under acceleration that is special to a five pot engine and harks back to Audi's original quattro cars of the 1980s.

Let it loose and 0 to 60 comes up in just 5.2 seconds which is almost as quick as a V8 powered Range Rover Sport. The top speed is restricted to 155mph yet despite the pace Audi claims it can return 32mpg with emissions of 206g/km.

Fitted with a seven speed semi-automatic box with paddle shifters for manual changes, the RS Q3 can move swiftly through the gears and on our run we managed to average a creditable 29 to the gallon.

Priced from £41,735 it is the flagship of the Q3 range but the cheapest of the seven RS models Audi now produces.

Dressed up with sporty body kit including a sculpted rear spoiler, plenty of RS logos and a quattro emblem emblazoned across the base of the grille, the RS Q3 sits an inch lower than its regular counterpart.

Sports suspension produces a slightly stiffer ride but it is by no means harsh and the steering has a good weight and responsive feel, although it did exhibit some slight understeer when cornering briskly.

For an off-roader it is surprisingly competent when put through its paces with body roll kept well in check.

Under acceleration some gear changes were not as smooth as they could have been but generally it feels well planted and sporty.

The car we drove came with black leather upholstery - and a black headlining - as standard but extras included hill descent control, sat nav, a hill holder to help moving off on slopes and cruise control.

In all there were £6,000 worth of options fitted to the car and some were surprisingly basic such as a load through hatch in the back seat for £175 and a reversible luggage compartment mat for £75. Even an auto dimming rear view mirror will set you back a further £295.

All in all it brought the cost of this RS Q3 to £47,520 yet even so it's still the cheapest RS you can buy.

Moreover, there's nothing else to match it. Top grade BMW X1s and Range Rover Evoques have nowhere near as much muscle and the bigger Range Rover Sport, Mercedes AMG M-Class and Porsche Cayenne Turbo are in a different league.

It's little surprise that Audi is predicting the RS Q3 will hold on to an incredible 52 per cent of its value after three years and 60,000 miles.

That's an unprecedented residual value for an SUV and indicative of the exclusivity which comes with this car. The school run will never be the same.