The front sway bar in the both the competition set and street set is the same stiffness, adjustable either 43% or 70% stiffer than stock. The rear sway bar in the street set is 88% stiffer, while the comp bar is 123% stiffer than stock. I have the comp rear bar in and it does tend to make the back of the car jar around a bit more on bigger bumps, but either sway bar would do that. The handling from either set would be worth it. The difference from the two would be the handling balance you would have. On street tires the car will definatly oversteer if you are not smooth and let off the gas quickly midturn. It is not, however, uncontrollable, it can be very usefull to help rotate the car in lower speed cornering, such as autocross or those tight freeway onramps we all love. I would assume with race tires the extra stiffness of the comp bar in the rear would keep a more neutral balance on the track.