I had 20% on a former red cavalier and I have no pics but damn did it look great. Very dark with the black interior but I did have many problems with cops at all levels...Sheriffs gave me the least amount of trouble but local and State got me anytime they could...Probably had about 10 warnings and 4 tickets in that car in only a few months before I was literally forced to take it off or face having my license revoked in court by the judge.
More recently I had 35% on the front and 30% on the back, which was dark enough and never had a problem with cops..I would get a feel for from others in your area with tint how the police are...My cousin has 20% all around his car where he lives in Vegas and has never had a single problem with cops in 3 years of owning his car....
Upload pics..would like to see how it turns out. Good luck.
I have 20% tint all around on my Racing Red Koup and I love it, I don't think I would have been happy going any lighter. It just looks great. Even the guy at the tint shop that installed it told me that adding the tints make the car look completely different and for the better. However for whatever reason I can't seem to find where the pictures I have with the tints done are.