got cited when i had my hks dual hi-power ti system in diamond bar. cop said "its too big" (w/e that meant..). when i took it to highway patrol, they signed off on it since it was quiet. cop at the station suggested that it "looked too pretty to be stock" which is why he thinks i was cited for it.
ever since i got the akrapovic system, cops don't give me a second look or tail me anymore