I have the Two Bros exhaust. They are ridiculously loud. Without the inserts, there's almost nothing but bass. And I mean annoying bass. Like a 5.0 Mustang with Flowmasters annoying. Just a loud, hollow bass drone. At idle, and just above, I could hardly stand to ride the thing. With the inserts, they sounded PERFECT, only still too loud. All the inserts do is castrate the low RPM bass, and quiet them down a bit. Still too loud for my taste, but that's just me. And yes, you will wake up the whole damn neighborhood with the TB's and no inserts. With them, you can go slow and short shift, keep the RPM's down, and probably only wake up every other home. lol