I get stopped from time to time..........granted it is only the one county who screws with me, and I have 20% all around my car, but looks darker because it is a black car.
I say if they are strict on the shit, then don't go ligther than 20%. I feel if mine was much darker, they would write me up! I have been pulled over 3 times in the last 2 months going to visit my mom. I have it down to a science now........I think. If nice out, roll them all down, lol! If not, take the back roads........if I still get stopped, ask the baby to cry on cue, lawl! Seems to work thus far.