I watched James Martins reviuew of this monster a few weeks ago out of curiosity
The running costs would be truly frightening. These are heavy and complex machines which sold in limted numbers, they would eat through tyres/brakes/diesel. I don't know how many bespoke parts Audi used but I would expect some of the driveline components to be unique and therefore outrageously expensive if you're unfortunate to have a failure.