First thing that comes to my mind is cost and profits. I had my front door windows and a strip on the windshield tinted on my '11 Explorer because the others were factory tinted. Now I'm thinking the factory tinted windows may not block the heat as good as aftermarket tint. One thing is for sure now, I'll never skip the windshield again, and I will double the tint with aftermarket tint on the factory tint until I know they block the heat like the aftermarket tint. I always get the highest legal quality tint, but this Air Blue is unbelievable on these large windshields.
If you say this stuff can reject the Florida heat baking the car, I'm now very interested in applying it on my San Diego NRG. I park at work in the sun and even with the windows cracked and a sun shield I always find the afternoon sun has heat soaked the car.
Tint King says it will block 43% of the heat. They told me to park with my windshield facing the sun for a few days for it to dry before coming back for the strip at the top. I got in about 3pm to see how hot the car was, and it was about 105F, but I had all the windows up. Normally, without Air Blue, it would be above 115F inside the car, and take much longer to cool down the interior. I thought if I had cracked the windows like you say, it would have been about 98F inside the car. Not bad with the OAT at 90F. The big thing is how just opening the windows while driving cools the interior heat to just above OAT without the A/C. Before, the interior would stay at 98F and above the entire drive with a heat soak of 115F with the windows down with an OAT of 90F. Thing is, I can stand turning off the A/C with Air Blue to increase my range to make it back home or to a charger to get home in EV. If the NRG is 10F cooler, the battery in going to be cooler and more efficient.
Don't forget, you can still use your sun shield while parked, but once that heat makes it through the windshield in that space between the shield, it's in the interior already. Tint King has a test lamp that you can put your hand under to feel the heat. Then they give you a sample of Air Blue on a small piece of windshield to put in between the lamp and your hand. It's like night and day how much heat is blocked. The strip at the top of the windshield is for direct sun glare in the mornings and evenings, that's why they reinstalled that over the Air Blue.
I'm thrilled to death about having a much cooler car to drive during my hot summers now. That NRG hugh windshield is no longer a pain from the sun anymore.