I have Formula One Pinnacle 30% on all the windows, and Llumar Air80 on the full front windshield, and I love this combo. It blocks out more heat than standard tint, and honestly, 30% is plenty on these cars. Dark interior combined with the small cabin make it look just right.
I had 15% on my old Toyota Avalon, and though I loved the privacy, it was a pain at night.