Not real sure I've heard you lose a little Hp with shorties NOT REAL SURE THOUGH... it also depends on what you like, some like the shortie look some dont. If you are goin with the shorties i would lower the bike, i personally dont think it looks right with them on and not lowered, it looks like somethings missing. Just my opinion...
here are my tailwindz. i don't race my bike so i don't need every little horse.
it sounds the same with them on or with just the cats just get the chrome tips and put them on...