Super trapps are not that loud.
Unless you get open end caps.
And even then. A kerker with comp.baffle. Will always sound better.
Everyone loves the sound of a kerker 4 into 1. It makes heads turn. Then there's the fun of. Riding through a parking garage. It sets off car alarms.
Pfuhhh! 'car alarms?' I was inside a parking garage next-to a bank branch entrance, and when I started my Kerker 4/1-equipped bike,
the bank alarms went-off! I didn't stay around to see 'why.'
I had a UFO 4/1 system on my bike for Daytona one year, with the balogna-cut diffuser, which is pretty-much a straight-through tube with a wide-diameter perforated cylinder inside it, which does very-little to quiet things. Marcus was there, we all met at Boxenstopp's for the Sat. ride to the Deland Airport for a lunch at the restaurant on the grounds, and Marcus made sure that when he was riding by me, he was on my
left. "Too-loud," he said. It was. I later added a literbike exhaust to the UFO header pipes and collector, which quieted things down considerably.
I have a Supertrapp SS 4/1 exhaust for another bike, my FZR1000, and it's a good product. If you run a lot of diffuser discs for the Supertrapp, I believe you won't think it's too-loud.
Drilling-out the OEM megaphone exhaust rivets in the end, and then drilling a few 1/2" holes, and re-fastening the disc will make the bike a bit-more-throaty, without making it excessively-loud. Space it-out, so the 1/2" holes 'work.'