Our laws here in the UK are a little different. If you get pulled by the plod, they have a special electronic gizmo which checks how much light is going through your windows. On the front side windows you need to have a minimum of 78% emitted light, if you haven't then it's seen as a defect and you have to remove the tint. However, on the rears you can have what you want. I personally run with limo black tinted rear windows with no tint (other than factory) on the front. Although our vehicles go through an MOT here, I don't believe it's an MOT failure to have tinted front side windows.