THE Audi RS5 is an understated coupe with the very best of supercar credentials and a growl to die for.

Start up the fire-breathing 4.2-litre V8 and it will waken the neighbours two streets away.

It's like those sixties American muscle cars beloved of Carroll Shelby, and of Steve McQueen in so many film roles.

If you have even the slightest whiff of petrol in your veins, you'll find yourself searching for tunnels and underpasses and will open the window just to hear the music echoing back from the concrete.

But unlike the lazy V8s in those classic muscle cars, this one likes to rev, delivering its maximum power at a heady 8,250rpm.

The RS5 manages 0-62mph in just 4.6 seconds, with a governed 155mph top speed, and is the most economical (26.2mpg combined) and carbon-friendly (252g/km) in its class.

It gets its power on to the road with the aid of Audi's S-tronic twin-clutch transmission and the customary quattro four-wheel drive - 30 years after the first Quattro took to the streets.

The driving position is excellent with plenty of adjustment but the offset pedals do not help long-distance comfort. The dashboard is very busy and the controls a bit fussy, and the angled rear window and high sides affect visibility.

: BMW M3