The A8 is competitively priced next to the BMW 7 Series and Mercedes-Benz S-Class, undercutting them slightly even before you take into account the standard four-wheel drive. However, its CO2 emissions are some way behind those of the competition, so will deter company car drivers. Thankfully, the hybrid A8 e-tron, which will go on sale later next year, should go some way to correcting this imbalance. The S-Class will be a cheaper proposition on PCP finance, though.
There is still cause to be wary, because the resale values of these big limos are notoriously bad, dropping up to half of their list price – or sometimes more in the case of top-end models – in the first year alone.
The 50 TDI diesel is claimed to deliver up to 50.4mpg, while the 55 TFSI is some way behind on 36.7mpg. We haven't yet run our True MPG fuel testing on either, but expect the real-world figures to be somewhat less. A motorway run in the 55 TFSI, for example, returned around 27mpg – about what you'd get from a Mercedes S500 petrol.
Standard equipment is very generous. Even on entry-level cars, you get 18in alloy wheels, leather trim, 22-way electrically adjustable and heated front seats, all the infotainment kit you could want, leather upholstery, LED headlights, Audi's Virtual Cockpit digital instrument display, a powered bootlid, air suspension, adaptive cruise control, a head-up display and dual-zone climate control.
Long-wheelbase models add heated rear seats, a 5.7in tablet-style remote control, four-zone climate control, rear USB ports and electric rear sunblinds.
Unfortunately, the headline-grabbing Traffic Jam Pilot system isn't ready for production yet. And even when it is, its introduction will be subject to the technology being deemed legal. Audi claims the system will be rolled out in 2018.
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