Estate fans, this one's for you.

The proliferation of crossovers and SUVs has had a negative impact on demand for estates, but Audi believes there’s still a market big enough to justify selling Avants in different flavours around the world. In the attached footage shot in sunny Malibu by Auditography we get to admire what is arguably Ingolstadt’s most desirable estate ever, the shiny new RS6 Avant. It wasn’t all alone on the streets of California as it was joined by a truly special car – the S4 Allroad.

Wait, Audi has never built an S4 Allroad, right? That’s true, but this one-off creation is the closest thing to an official rugged sports estate carrying the Four Rings. Our idea of an interesting hybrid, the car is the result of fusing a new A4 Allroad with the engine borrowed from a new S4 Saloon. It took a talented engineer named Tyler Setterstrom and some 150 hours of work to make it happen, and the end result is just as radical as the new RS6.

Gallery: Audi S4 Allroad and RS6 Avant

The S4 Allroad is special for another reason as its turbocharged 3.0-litre V6 engine has been upgraded by the tuners at ABT and it now pumps out a healthy 500 bhp or 91 bhp less than the RS6 Avant. Towards the end of the video, we can see the unique Audi estate in a short acceleration test, needing a mere 3.9 seconds for the 0-60 mph sprint and 11.98 seconds for the quarter-mile run, at 115.63 mph.

A couple of reports published by German magazine Auto Bild in 2015 and 2016 said something about Audi planning to build an RS6 Allroad, but it never materialised into a production model. Seeing this unofficial S4 Allroad gives us hope that sometime in the future, the obsession premium automakers have with creating niche models will lead to the creation of something along the lines of a lifted fast estate. They certainly wouldn’t be any less interesting than those SUV-coupe mashups…

Source: Auditography