This new upgrade program for the 2010 Audi RS6 includes Sportec components and offers customers a two stage conversion for the already sporty German estate.
With the stage one conversion priced at 2,800 GBP, the Sportec 2010 Audi RS6 receives a power boost thanks to an ECU optimisation, so it means that instead of 572 BHP (426 kW) and 479 lb-ft of torque, the car is now able to output 650 BHP (478 kW) and 740 Nm (540 lb-ft) of torque.
As far as the Sportec 2010 Audi RS6 stage two conversion the car’s new power level will be 700 BHP (515 kW) and 800 Nm (584 lb-ft) of torque, for which speed addicts will have to pay 6,500 GBP.
The Sportec 2010 Audi RS6 stage two is able to sprint from 0 to 62 mph in 4.2 seconds while maximum speed is limited to 190 mph. 
APS Sportec press release :
APS of Brackley, UK importer for the Swiss Sportec range of
prestigious vehicle enhancements, is delighted to announce the launch
of a new performance upgrade program for the 5.0-litre,
twin-turbocharged, direct injection, V10 Audi RS6.
From the factory, the 4F model of the Audi RS6 produces a mighty
572bhp (426 kW) and 479lb.ft of torque. Impressive as this may sound,
Sportec’s qualified technicians have identified performance enhancement
opportunities on the RS6, which has translated into two new upgrade
packages now available from APS.
APS Sportec Audi RS6 Stage Two conversion
Anticipated to be the more popular of the upgrades, the APS Sportec
Stage Two conversion consists of an ECU remap, complete with
performance optimisation of fuelling, ignition and boost parameters, in
parallel with the fitment of emissions compliant sports catalysts.
Post conversion this increases the RS6’s outputs to a fearsome
700bhp (515kW) at 6200rpm, allied to 800Nm (584lb.ft) between
3000-6200rpm.
In practice this translates to a stunning 0-62mph time of 4.2
seconds, combined with a limited top speed of 190mph – where conditions
allow.
Suitable for both saloon and Avant estate versions of the Audi RS6
4F, the Sportec Stage Two upgrade is available now from APS of Brackley
priced at £6500 Including fitting and VAT @ 17.5%.
APS Sportec Audi RS6 Stage One conversion
For those with milder tastes, APS is also pleased to offer the
Sportec Stage One upgrade for the Audi RS6 saloon and Avant estate
variants.
An ECU only upgrade, this conversion increases the Audi’s power to
650bhp (478kW) at 6300rpm, coupled to 740Nm (540lb.ft) between
2500-4000rpm.
On the road this enables the APS Sportec converted RS6 to reach
62mph in 4.4 seconds. Top speed is limited to the same 190mph as the
Stage Two conversion, where allowed.
Priced at £2800 Fitted including VAT @ 17.5%, the Sportec Stage One upgrade is available now from APS of Brackley.
A full range of Sportec Audi RS6 enhancements, including alloy
wheels, braking and suspension packages, will be launched by APS of
Brackley over the coming months.

Source: APS Sportec