I'd go with spartanking.Car 2000. Close to Sanaa roudabout. Got my car done for 60QR. very light tint in the front windows and dark tint in the rear.This is for my wife's car. No tint can put on the windscreen and back glass/boot glass.

Important Suggestion - The black tint in the rear passenger windows are very dangerous while driving - it creates additional blind spots especially while driving at night or when one does not have a passenger to guide you.So put in a cheap tint so that you have an option of removing the same incase it becomes too difficult to drive. Its all a matter of taking extra care then and driving carefully once you are used to it.

The expensive tints should be put on the front driver and front passenger. Not worth it all around unless you intend to spend quite some time in Qatar. V Cool, P J's etc all good. They really do block the heat/UV once installed but then again you've got a huge windscreen to let the heat/UV rays, so i considered it useless.These would be effective if installed on all the windows of the car (safe too cause they are transparent). However this is not allowed in Qatar