I guess we had the opposite experience with an aluminum roof. We had a 1988 Jayco 2850 FW with an aluminum roof. I barely maintained it, and it never had a problem for the 15 years we owned the trailer and stored it outside through 15 Michigan winters.
Actually my experience came from working on dozens of different aluminum roofs of all ages over several years period and not just owning one RV with a Aluminum roof.
Trailers in places like NM/AZ southern CA where the sun is intense have the greatest stretch/shrink problems that gave the old galvanized steel and later aluminum roof material the greatest maintenance issues.
