Bought a 1968 280SL from the original owner, who never knew the hardtop could come off. Not only that, the hardtop was never taken off the car, evidenced by the buildup of paint under the chrome strip along the bottom edge of the hardtop. There were 3 repaints and the original paint was still shiny under the hardtop and inside the car.
The softtop was the original one with a clear plastic, but it was all dry and dusty.
Naturally I wanted to put it up, but it shrunk from lack of use in 21 years. Latched the front and the rear was not able to close, so I left it out overnight for a good soak in the rain. Then closed it in the morning, easily too. But wanted to clean some of the dust of, and the scrubbing brush went right through the fabric.
So the life depends on the care and treatment it gets.
Walter
1967 220SL-diesel-new German Fabric top since Oct. 2005