After reading all 10 pages. Looking at various photos on this forum and Google pictures. It seams that almost any muffler sold by Corsa could be claimed to have "rsc".
The bigger question is not what muffler system is used or not. But DOES IT WORK AS ALLEGED? Should be pretty darn easy to place a dB meter in the car and prove the lack of drone of not. Heck even a smartphone app can be used to record sound waves and prove drone is decreased or not. No need to cut up a muffler. Just drive the car and record sounds!
The bigger question is not what muffler system is used or not. But DOES IT WORK AS ALLEGED? Should be pretty darn easy to place a dB meter in the car and prove the lack of drone of not. Heck even a smartphone app can be used to record sound waves and prove drone is decreased or not. No need to cut up a muffler. Just drive the car and record sounds!