Butt Dyno says marked improvement. Installation was pretty straightforward after all the broken satan studs were removed. Installed, warmed the ran the bolts again. So for I've got about 300 miles since install and I'm a happy man. Feels like it takes less pedal to get around, I guess that's the best way I can explain it. Thanks to all that took the time to do write ups and answer questions before and after purchase.