I've never owned a fiberglass trailer and I've only owned the aluminum sided trailer that I currently have. I've always felt the fiberglass trailers looked nicer, sleeker and classier, but I had an incident that made me realize I will never own a fiberglass trailer as much as I would love to. I peeled open the side of my trailer like a giant can opener was being used on it a couple of years back. The total cost to repair was under $200 replacing two 12 foot long pieces of siding and an hour of my time. Try to do that with a fiberglass trailer!