I am more interested in UV blocking and heat blocking than anything else. The darker probably the better (people can't see inside your car and steal your stuff) if it actually reflects heat as opposed to absorbs it. Good call about being cool with the cops too, making their job easier makes them be easier on you. The City of Milpitas California has a "tuner" section written by a cop that details exactly what traffic cops look for when they pull cars over (not all cops are assigned as primary traffic duty), the mods and such. Anyway, my car is black on black which is fine in Monterey (70 degrees) but it sucks in Sac (90+ degrees).