Originally posted by: alkemyst
I like moonroofs in the cars I cruise in...the cars I play with I try to get a solid roof for chassis stiffness.
The roof panel has about as much stiffness as a piece of aluminum foil regardless of whether it has a hole in it or not. The added weight up high in the car would have a much larger effect on handling than a tiny reduction in stiffness of a floppy thin piece of sheetmetal. You might as well buckle all the seatbelts in your car to "tie down the chassis" and increase the stiffness.
Slight off-topic, but Honda excluded the moonroof from the otherwise top-of-the-line Accord Hybrid because they wanted to cut down on excess weight.
Personally, I love the moonroof in my car. There is a ribbed diffuser that pops up when it is open that really reduces buffeting and noise. It's a great way to get sunshine and fresh air at 80 MPH without blasting it right into my ear and drowning out the radio. I especially love it on the way to work, with the cool morning air and sun waking me up. Even at lower speeds, I often choose it over opening the windows, because you hear so much less of other cars, stereos, motorcycles, etc. If I just want a little, I use the tilt feature. There are times when I don't want the sun in my eyes or I want maximum quiet in the car, and then I just close it and the shade.
Think of it as the middle-ground between a closed roof and a convertible.