I think there is one good thing about having moonroof

During the hot summer days, the top of the car (any car) will get really hot under the sun. If the car roof is too close to your head (it depends on the car design and your body size), you will feel the heat, and it will take long time for the air conditioning finally cools down that part of the car. The moon roof (glass material) insolates the heat better, and openning the roof will let the hot air leave the cabin much faster after letting the car sitting under the sun light for a while.