What is it?
Audi has always done a good job of filling niches you didn't even know were there. With the new RS4 Avant, it's (big) business as usual.
It's not until you really get going that the RS4 starts to make an impression. Grip is phenomenal - especially in long, loaded-up corners - with the kind of burly, slightly understeer-prone attitude that gives lots of confidence in the wet. Poke in a bit more throttle smoothly, and you can even make the whole thing oversteer (there's a self-locking crown-gear centre diff that helps with the feeling), though it's not rear-wheel drive and never really feels like it.
Essentially, the RS4 feels quite firm when pottering - even in Comfort mode - but the 'box slips between ratios without a murmur, the engine mumbles away happily and you could be forgiven for thinking you're in a more humble S line variant.
Up front is a naturally aspirated, FSI direct-injected 4.2-litre petrol V8 that produces 444bhp at 8,250rpm, a red line at 8,500rpm, and with maximum torque of 317lb ft available from 4,000 to 6,000rpm. Basically, the same engine as the RS5, plus a few tweaks, it drives through the only transmission option: Audi's 7spd S tronic dual-clutch 'box. Which is interesting. An estate car with a super-high-revving V8 and slick-quick DSG? Sounds like a TG kind of car.
On the inside
You'll get 490-litres with the seats up and 1430 with the back folded down, so there's plenty to play with as long as you're not into HGV-style loads.
Supercar-style insurance and a claimed 26.4mpg - less if you drive it hard. A lot less. If you can swing one on a company car scheme, we'd like to work there too.