I ran 70% windshield and 20% all around ceramic on my black e63. It was a little dark at night, but it kept the heat out during the day. It was dark enough where I didn't have to wear sunglasses.
I ran 68% on the windshield and 35% on the front sides (the rear sides were done by the dealer, but I forgot what it was) on my Raptor and same, it was a little dark at night, but perfect for the day.
I've only done the windshield on a couple cars. I did a clear one on my first raptor and it really bothered me. I could always see the film and it messed with my vision. I went back to the shop and he replaced it with the lightest tint, roughly 68%. It was amazing to have. It helped with heat a lot, especially in the summer. The car would cool down a lot faster. It was easier on the eyes. It was a gamble when I got it, but it helped a lot where I live.