My ford pass/rear glass is 17% from the factory. Says so right on the window stamp. VLT 17%.
I had the fronts tinted to 15% to match-ish and the windshield tinted to 50%. I was very worried about how dark it would be as I have had old dyed tint and it was hard to see out. The new ceramic stuff is great and does not really impair the view that much. Its so nice to not need sun glasses anymore.
Have a few LEO friends and they all hate traffic stuff. Will only pull over for serious stuff. Might be an addon charge in that case.
I was advised if pulled over roll down the windows to put the officers mind at ease.