I've seen the cautions about tinting upper glass on the M3. I would like to hear real experiences of those who have had problems and those who have done so with no issues. I installed the screens right after I got the car, but now that our Florida sun is getting more direct I doubt that they will do much to reduce heat buildup in the cabin. My car is not garaged. I know this is a common thread, but I am still undecided. Believe me, I have read most of what has been posted on this subject. So, forgive me if this is beating a dead horse but I would appreciate a little more help here. Also, experiences with interior and exterior windshield films. Thanks.