Basically, the cops don't know the ****ing laws they're supposed to be enforcing, and if they can't find a real reason to defect you, they'll invent one.

Having said that, I find that as long as you aren't stupidly low, don't have ridiculously oversized wheels, don't have an obnoxiously loud exhaust, and don't have a stupid rear wing, you won't receive that much more attention in any car. If you're getting police attention in a family sedan, there has to be a reason for it.