As you are looking for coaches that are 15-22 years old, I'd be more concerned with overall condition and care of the coach than roof material. All roofs, regardless of material, have holes in them to allow for vents, AC's, Antennae's, sky lights and seams. Usually leaks develop around those areas and not failures of the material itself - sans actual damage. Any coach you buy of that age will require a very thorough inspection by someone qualified and if it checks out, the roof material shouldn't be a deal breaker. Roof materials all have their plusses and minuses. Sure fiberglass roofs are great but they aren't without their own share of failures. Fiberglass can develop cracks - especially after 20 years and are exponentially more expensive to fix or replace than a Rubber or TPO roof. And there are countless TPO, Rubber roofs out there that are 20+ years old with no issues.
