This is just a quick question I have recently heard from another residential roofer. He told me that the shingles are applied and job is complete, it takes Owens Corning shingles 3-4 weeks to properly seal??? He said GAF seals immediately. This was on the 30 year dimensional. Which is a better quality and not just which one will make you a Platinum Certified Gold Member for pushing they're product. Is Owens truly a bit better quality and is the sealing deal a freakin' hoax??? Thanks folks!!