If you get the dealer tint they will will mostly want to tint the windscreen , a lot of good comments here regarding night vision.My wife wanted 60 all round and I compramised on 50 with 40 on the windscreen which I wasn't to pleased about not wanting any tint on the screen, another problem they can put the cheap tint on which has the tint logos imprinted on the tint ,annoying if its right in your line of sight on the screen , We got free tint from Honda which lasted 3 years before it faded to clear , you don't notice it happening but if you roll down the window just enough to see a thin black line around the glass where it fits into the felt, I put 3M tint on after the dealer <deleted> faded for around 3k including removal of the old stuff with no logos and came with a 5 year warranty