Residential homes are made of wood and often last over a hundred years. Just sayin'. Some of the best trailers have wood trusses. As with anything you own, if you don't take care of it, it might not last long. There's nothing inherently wrong with rubber roofs either, except that they may be more prone to punctures or rips. They're easy to repair if that happens. This particular subject usually boils down to manufacturing quality, not materials. There's plenty of threads around here to prove that those with no wood or rubber suffer show stopping leaks too.
The unfortunate reality is, as an owner you better expect to be doing inspections and preventive maintenance from day one. (Unless your favorite floorplan fits in one of those few trailers that don't have any wood or rubber, which totally eliminates the corrugated aluminum sided units)