By any objective measure, this is an exceptional machine. A downsized engine combines effortless reach with an elemental punch that will be alien to owners of the old V8, and the quattro chassis conjures such stability that you suspect the RS4 Avant would simply drive away from its rivals on any road that was less than immaculately surfaced.
Fuel economy is also vastly improved, and the interior hits new heights in ergonomics and quality. There are limits to what this car can do operationally, but they are so high as to be redundant – and so Audi, somewhat understandably, will congratulate itself on a job very well done.
So why only four stars? The reality is that there has never been an RS4 with a less identifiable character than the B9 tested here.
The thin-voiced 2.9-litre V6 takes a large share of the blame for that, but the design – a touch contrived and corporate – is partly responsible too. Mesmerisingly competent it may be but, in contrast to one particular compatriot, it fails to quicken your pulse at anything other than terrifically high speeds.