I have always been told that just a exhaust "canister" upgrade/change does not require a re-map of the ECU, but a full exhaust does... Am I wrong?
You don't "have to" do anything. If you just replace the slip ons or both headers and slip ons and Your bike will still run. But don't be too upset when it has a horrible fuel/air ratio and all you hear is back firing and sputtering while the throttle is opening up and closing.
I couldn't find anything for the M1200 from these two companies either.
Notwithstanding, as @phantom menace and others mentioned on another thread, I'm questioning the dollar value/improvement for devices like RapidBike when just adding a slip-on as I have done.