After reading numerous threads on these...I decided to try one for myself.
Most complaints people had about these was about excessive vibration.
I guess im not as sensitive or my car took to the mod better because I feel only a slight and low rumble and a little vibration on the gas pedal. What I got in return was a much better response off the line and smoother shifts in every gear. I love the way it feels, even the vibe...makes it feel more like a racecar. If I wanted a smooth and cushy ride...I would have kept the whole car stock. I highly reccomend one of these!
-My 3 cents