A new U.S. tuner plans to launch its operation with a highly modified BMW M6 Coupe (F13) tuning program, on the M6 which they've called the Risden 6R.
The Risden 6R M6 coupe features a functional aero kit, the most prominent part of which is the double rear trunk spoilers - one is the fixed duck tail CSL style spoiler, while the other is a retractable spoiler, deployed when needed to improve downforce and stability.
The 6R is also said to feature a fully adjustable suspension system, rollcage, and stripped down interior. The overall goal is to reduce the car's weight, while adding a stiffer chassis/suspension and increasing power output.
So, it appears that the Risden 6R has been designed for track use and not just for looking like a track car on the street (or so we hope).
More details will come in the first quarter of 2013.