Audi RS6 Avant (C7)
Why 7.0: The generation that made the fast Audi estate a mainstream object of desire: 560 PS, 700 Nm, 0–100 km/h in 3.9 seconds, air suspension as standard and a boot that swallows a family. Audi sold Americans the RS7 Sportback instead and left the wagon in Europe.
Layout
Natural habitat
Ride comfort
Sound
The 4.0 TFSI has a proper deep V8 foundation and the sports exhaust cracks hard on the overrun. But the turbos live inside the vee, a sound actuator and the speakers fill the gaps, and the theatre is switched on rather than earned by the engine.
8-cylinder · turbocharged · 6,800 rpm redline · rated 5.9 / 10 for engine sound
Market value
Median asking price, good condition · €100k (2014) → €53k (2026), trending down · illustrative data
Child seats · ISOFIX
Two ISOFIX positions on the outer rear seats, the outer pair being the ones the standard covers.
The rear anchors are the supported route — the manual points child seats there, and front-passenger ISOFIX is the exception rather than the rule. A belt-mounted seat up front needs the airbag off, and cars with a rear row don't always fit a deactivation switch, precisely because the rear seats exist.
Derived from production years and seating layout, not a per-car source. ISOFIX was standardised as ISO 13216 in 1997, required on new EU model types from 2011 and on all new EU cars from 2014.
The long version
The C7 is where the RS6 became the default answer to the question of what one fast car should do. Audi dropped two cylinders relative to the C6's V10 and gained performance anyway: a 4.0-litre twin-turbo V8 with the turbochargers inside the vee, 560 PS, 700 Nm from 1,750 rpm, an eight-speed Tiptronic and cylinder deactivation that shuts down four cylinders at a cruise. It runs to 100 km/h in 3.9 seconds and rides on air suspension, which is the combination that made it credible as a only-car. The 2015 RS6 performance raised output to 605 PS. North America got the mechanically identical RS7 Sportback and no Avant, a decision Audi did not reverse until the C8. Depreciation has been steep and predictable — new-price six figures, half that within six years — and because the cars are so genuinely usable they cover real distances rather than sitting still. That combination is the honest case for this generation: it is the rare fast car whose owners have no excuse not to drive it.