I have them and am not really worried about anyone seeing them. The only time it would be a problem here is during annual vehicle inspection and I am reasonably sure the guys I go to have no idea the car had precats and even if they did you can't see the headers that well. I have never had a police officer even look at the engine in any car I drive so it shouldn't be a problem. As long as you keep the main cat on the car it is still very quite and shouldn't draw any unwanted attention.
