The first installation caused a misfire. After reinstalling and going through 4 drive cycles (which I originally did not know I had to do), the car is running better. I have to let the car warm up before driving now for a smooth ride. There is no difference with the acceleration off the line and the turbo does not spool faster as Hondata states. The gains are amazing and I consistently beat the stock 2017 Si without any issues. I am really nervous about the previous misfires and every time i accelerate from a stop it is all I think about. I feel a custom tune would have been more safe, but my Honda service manager said I can just uninstall the flashpro before servicing the car if there are any issues and the warranty should still cover everything, therefore flashpro is better bc a custom tune voids warranties. The torque and horsepower gains are amazing though, especially on cool nights. I cant wait until I drive in the winter. Also, Affirm financing was the reason I actualy went with the flashpro. They are great!