nascar, rockcrawler rims
I have 5% on the rear 3 windows, and backing up at night is a religious experience. 35% on the front doors is kinda too light for my taste, but it's legal.
It's the darkest legal limit, but I really do need to add some supplemental lighting. It really is nice to keep tailgaters from blinding you, or to hide your stereo from prying eyes.