Just purchased a 18' ES and was experiencing the surging while accelerating that is famous with our cars. To correct this issue I went ahead and purchased SXTH Elements Hot Pipe Upgrade and Pierburgs Wastegate Solenoid Upgrade. I can see why everyone says these mods are a must have. 😃 No more surging and car has a much more responsive throttle pedal. Thanks for all the great info the community has gotten out there.