This is my feeling on it in Michigan, without being to tint the fronts at least a little bit, it feels weird. On my old car that had very dark tint in the rear windows from the factory, I would ALWAYS roll down all 4 windows all the way unless it was pouring and even then I would still roll them down a bit.I'm posting this to help others decide how dark they want to go.
I'm a cop. Most of us use window tint as probable cause to stop a vehicle. Just because you are stopped doesn't mean you are getting a ticket. Most of us are looking for "real" crimes i.e. Drug use, Driving Under Suspension, DUI/OVI, etc.
If you are polite, roll your damn window down so we can see you if you have tints, and don't have any other violations going on, you are likely to get a warning. The biggest thing is being polite (and not having a bad driving record).
Obviously we're not all the same and some cops are simply ticket Nazi's but the majority of us are just normal people that are trying to get off work so we can enjoy our other hobbies. Don't make us nervous by being angry your got stopped, or not rolling your window down. When I can't see your hands the only thought in my mind is "when is he pulling the gun". Treat any human being with respect, and chances are you'll get some back. But play stupid games and/or have stupid excuses and you win stupid prizes.
Long story short, if you have illegal tint, expect to get pulled over so don't do anything else stupid like drive drunk and you more than likely won't get a ticket.
And we're not stupid either, we know that most car culture people aren't criminals and are usually sober (because their money was spent on their ride and they don't have cash for booze and drugs).
Obviously YMMV and cops in your area may be different so take this for what it's worth. IMO, get w/e tint you want, just expect to get pulled over for it.
And FWIW, I have never personally stopped anyone for window tint (or seat belt violations) because I think they are dumb laws. Sorry this is so long. End rant.
Every single time I did this, all but one cop thanked me for rolling down the tinted windows, I understand this from a safety point of view, and I know you're just doing your job.
That said, I will likely tint the front to 50% and rears to 35%, leaving the fronts stock seems so weird to me on a sedan.