I’m prolly more mature than most Si owners so I look for function as well as form. This exhaust has changed the personality of my 19 Si! It feels more like a 2.0 than 1.5. The change is especially obvious in the mid range and top end, from speed limit to triple digits is so quick now. Yes, it gets boomy at around 3,000 rpm and it’s a little louder than I’d hope for, but it is just awesome. Never thought I’d b this happy. I have vast experience with Honda and Acura and I know generally speaking, aftermarket parts usually only end up diminishing ultimate performance, as these cars are designed and engineered so well. The “straight thru” exhaust is free flowing and opens up the lungs of this little sweet heart; works great with stage 1 tune!