I think it would have the effect of a magnifying glass on your head. And what would it cost if it broke? Insurance companies wont be happy. People spend a lot of money in this country to keep sun OUT of their vehicles. Would the dragstrips treat the car as a hardtop? Its just something I personally would not be interested in.

 

T-top Fbodies are considered hardtops at the strip. Why wouldn't a glassroof Mustang? Both have a heavy structural frame over top the occupants...