What are the differences between drone props that are built from fiberglass-reinforced plastics and props made from polycarbonate?
The main differences are:
Fiberglass-reinforced plastics: Very stiff for their weight which allows the propeller to keep the correct shape and be more efficient regardless of how fast it spins (less prop flattening), but when these props hit something hard, that stiffness means it will shatter and the drone won't be flyable. Fiberglass-reinforced props are also not very susceptible to heat which is good and means that they will continue to be rigid and efficient in very hot weather. The brittleness of these props means that it is not likely you will be able to use Turtle Mode successfully very often.
Polycarbonate: Good stiffness and will bend rather than break if it hits something hard. This means that when you crash, a blade may bend rather than break and can often be bent back into shape. Polycarbonate props, however, are susceptible to temperature and will become brittle and can shatter if it is very cold and can become soft and not efficient of it gets too hot.