I think leaving the cat and going straight pipe after that is the ticket legality wise and sound wise. I seriously doubt that little resonator is doing anyhting with the cat and the muffler removed.
Mine isn't a Mega, but same wheelbase, cat and straight pipe. Sounds great, no drone, hardly any extra noise at cruise, even with a big load. Sings when you get on it though.
Pretty brave living in CA and removing the cat![]()