Audi RS6 Avant (C8) versus Mercedes-AMG E-Class E63 S. 0 points of retained value between them.
Both cars start from the same premise — twin-turbo V8, four-wheel drive, devastatingly fast estate or saloon — and both have come off their inflated new-car prices enough to represent genuine value today. But the numbers do favour the E63 S at the point of purchase. At £167 per horsepower new versus the RS6's £183, and with a power-to-weight advantage of 305 bhp per tonne against 279, the Mercedes was the sharper deal on paper from day one. It's also quicker in a straight line by a meaningful margin — 3.3 seconds to 62 mph isn't just a stat, it's a different sensation. Where the RS6 fights back is in what the money actually buys you to live with. The Avant body is genuinely useful in a way no saloon can match, and there's something about the way it disguises its performance — the understated silhouette, the effortless surge — that the E63 S, for all its discretion, can't quite replicate. The AMG is ferocious; the Audi is quietly menacing, which some drivers will value more on a drizzly Tuesday school run. Neither car has enough auction history to call a depreciation floor with confidence, so buy on character and cost today rather than gambling on future values. On pure value-for-money metrics the E63 S is the smarter purchase. But if you'd actually enjoy owning it more, the RS6 is worth the premium — and that counts for something.