I got 20% but found out that it is 15% from the cop when he pulled me over. He measured my front window. The back is even darker. Remember what ever you get it will be darker cause our cars come with tint, but you can't really notice it.

 

Expanding upon kdog's comments. If you get darker tints in the back your front tints will appear darker as less light is getting into the car overall.

I am happy with my 30% all the way around as I was looking more for fade protection on my interior with looks being second.

 

I'm in so cal and have 35% front/side and 15% hatch. It was a difficult decision because I really didn't want to deal with getting pulled over but after looking at the sample cars they had at the shop, I realized that 50% looks pretty much like the stock tint. The 15% on the hatch looks nice and dark at night, but during the day I actually like the look of a 5% limo tint on the hatch (I think it compliments the black glass roof well).