Hi guys. Just got my 950 SP today. Im looking at mufflers (slip ons). Im leaning toward the SC Project S1. I wanted Akra's at first but it seems the SC's are more popular. I also want the De-cat pipe. Do I need to remap or tune the ECU when getting the de-cat or S1's? What about K&N air filter? I would rather not retune. Not looking for speed AT ALL. Just sound. Thanks for your help.