Having a Corvette and a Firebird with a glass hood, I'm familiar with fiberglass body panels. There is an advantage/disadvantage thing with fiberglass:
Pros:
Fiberglass is a lot lighter. It is also somewhat flexible and will withstand door dings, etc., better than steel. It is also a lot easier to repair if you know how to work with fiberglass. Plus, fiberglass will not rust.
Cons:
Fiberglass is wavy by nature. It is harder to get as good a paint job on even a brand new piece, because you have to sand it smooth first. Fiberglass does have some "give", but if it's hit, it will utterly shatter. Fiberglass is also more fragile if you like to do a lot of off-roading. However, the kind of damage that will shatter glass will also put a significant dent in steel, so either way will need repair.
