Well, I found this article. Supposedly they tested cars with and without tint. This would be a good think for the MythBusters show.

http://www.coolnlite.com/TintMyth.htm

 

On a related topic, am I the only one who thinks the HCH-II air conditioning is somewhat weak? Even at the max cool setting, the air blowing out of the vent is not as cool as other car's air conditioning I own or have owned. It takes a lot longer to get the interior to cool down. Do I have a warranty issue here?

 

No. It's common on all HCH2's. You're compressor is run by the engine and the electric motor. Open the windows to blow out the hot air then leave the car on recirculate. No problems here in LA (temps ~ 85-90 degrees),
but I rarely use the AC.

 

You must really like heat!

 

I would imagine that there are cheaper tinting films that provide the privacy but not the cooling effect.

There are window films that work well for blocking heat.
http://www.edcmag.com/CDA/Archives/6...00f932a8c0____

http://www.huperoptik.com/Automotive.asp?cat=NaviAuto.inc