Fiberglass roofs

Each material has its advantages and disadvantages. As a young Eng It saw a lot of impact tests on FG structures. We used to drop 1/2 ball bearings from 20 ft and measure the damage to the surrounding structure. What was observed was a halo of cracked resin around each impact site. On .030 panels these would allow water to enter into the substructure. Without getting too technical if you dropped enough balls you could end up with a severely damaged structure. I flew into Texas one time and tried to rent a car and most were severely damaged by hail stones. I think this is what Doug was eluding earlier. Rubber or TPO would resist impact much better. I think the thermoplastic materials like the TPO are a good compromise between the high strength FG and the rubber that can be torn by tree branches. Having said all that I would not let roof material be a determining factor of the next MH I buy. My EPDM roof is 20 years old and has been patched in several places but does not leak. I just looked at two 2009 MHs with a one piece FG roof and the caulking was not maintained and there was leakage and a lot of water damage.