First rule in life, don't upset people who can upset you a lot more. Re OEM, it has been common place for years that if you buy OEM from places like Silvers in the UK they will often carry the US markings, it goes on the lines you will be shot if you alter the pipe by order of the president or some other Dept. of Transport nonsense. It's never an issue with testers but the classic officinado's hate them. Walk up to them at a show and point out to them that there claim that their bike is 100% original is not quite correct and the reaction can be startling. It's a bit like, light the touch paper and retreat to a safe distance.I concur with that thought. My guess is that once an inspector sees the word "Honda" on the silencer, they won't bother to look further, unless for some reason you have pissed them off and they are out to crucify you.
Michael
Upt'North.