Never owned a Syclone, but love 'em anyways. I do however own an STi. While I don't think the STi is "king of the mountain", stock for stock and with equal drivers, I feel it would be the STi comin' in first. HOWEVER, the STi will NOT respond to simple mods near as well as the Syclone. The STi's ECU is quite finicky. In order to make any serious hp/tq figures, you have to have some form of engine management, which can cost in excess of $1k for a programable/tuneable type. That being said, throw mods at each equally, and w/o engine management, the STi will go down HARD!....