I isntalled the Devil full system on m 690SM today. I also had my local dealership download the Akra map. Seat of the pants I can definitely feel a difference. Much more low and mid range power. The sound is excellent also. I decided to leave the baffles in because the straight pipes were just way too loud. The Devil system has excellent fit and finish. Enjoy the pics. Video w/ sound clip is on it's way.