Carbon emissions taxes and fuel efficiency requirements are throwing a bit of a wet blanket on the horsepower wars, especially in Europe, but the aftermarket is carrying on the battle with undiminished ferocity. The latest combatant is Vath's V63 RS Estate, a re-interpretation of the already impressive Mercedes Benz C63 AMG Estate.

For those that are thinking this sounds familiar, it is. Vath released a nearly identical tuning package for the C63 AMG sedan last year. Once the gang at Vath are done with them, both cars generate 585hp (436kW) and 510lb-ft (690Nm) of torque - up 130hp (97kW) and 66lb-ft (90Nm) over the stock values.

But even with all that power, the V63 RS is barely on par with a stock Audi RS6 Avant, though its 6.2L V8 is a very different beast than the twin-turbo V10 in the RS6. The V63 RS Estate also adds a small factory's worth of carbon fiber accessories, including hood, rear diffuser and interior trim, ensuring a unique look and improved performance.

Other performance upgrades include 20in alloy wheels, 9in wide in the front and 10.5in wide in the rear, to help provide the grip that all that power will need. High performance brakes are also fitted to match the engine's new potential, and the car's 202mph (325km/h) top speed.