Most people don't utilize them fully.

- In the winter, if there is sun, and you have like black leather interior, it actually helps warm the car up.

-For trucks, having a glass roof is almost essential for seeing if you will fit into a parking garage. Having lived in Seattle, Im glad my truck had one.

- Opening the roof and setting AC to use outside air is the fastest way to vent the car. It doesn't create as many vorticies as opening the windows.