I live in cali and 70% is whats legal on front doors here, well not to many people know that there is a legal tint here in cali. Anyway's I had the 70% on my suv and for the money it's not really worth it. But I guess you can say it somewhat blocks very little heat, but not enough because you'll still put you're hand out against the window to block the sun. It's CLEAR you can't even tell it's there. I removed it because it didn't do much for me and put 50% on the front sides and windshield, and you still cant tell there tinted. But I did get a ticket for the front doors a month ago (first time I drive it in months and I get damm ticket), the cop kept looking at me while I was driving I thought it was because I wasn't wearing my seatbelt, so he follows me and as Im getting home he hits his lights. Cop says your windows are tinted and illeagal, me being a smartass I tell him there 70% and they are legal. He pulled out a section code book stating no object material shall be apllied to windows or windshield, and stated that he use to work at tint shop. I said BS give me my ticket.
Sorry for the Long Story, but 70% compared to 50% or darker is not worth the time, but it is better than nothing, so if you don't want to get a ticket I'd just do the 70%.