I own fiberglass but will always take aluminum. Here is why. Aluminum panels can be replaced if need be from accident. Fiberglass pre fabs are vacuum compressed and sealed. Can one ever be repaired without compromising the area? Also al hides scratch's and do not need decals. Just an all around better choice in my opinion. Ever notice when the RV industry comes up with something new it is more than for them than for the consumer? Frameless windows? On what planet is this a good idea? Rubber roofing? pre fab walls? Just sayin