I've been in a ryan home for 5 years, and nothing has been wrong with it. I typically do a home inspection every couple years just to make sure there are no problems starting to occur, and there's been nothing.
House itself is about 12 years old. EVERY home builder is going to have lemons. And part of why people have problems is because THEY (the homeowners) don't take care of their home.
I will, and am in the process of, having them construct a new home for me. They build great homes with a 10 year warranty.