The combination of Suitcase X1 and Font Doctor has made my font collection basically healthy. Font Doc finds some bad fonts; fixes a few. Suitcase finds other bad fonts; fixes a few. I don't like Font Doc for organizing fonts, because the resulting collection is organized in a way that only a machine could find useful (too many folders, arbitrarily organized). I tried it and quickly trashed the results. But as a limited tool for dealing with some font problems I'm glad I have it and I use it.