Why bother with paid programs when you can get a free FontExplorerX from Linotype?
Depends on what you do for a living.
One other thing about Suitcase. This may not matter to a lot of people, but the main reason Extensis bought out Diamond Soft's Font Reserve was to get their hands on Font Reserve's "Font Sense" technology. This virtually ensures that the font used in a document is the one that will be opened during auto activation. If it can't find the proper font, it will let you know.
This is huge in prepress and publication. There are so many versions of Helvetica, Times New Roman and such around. Both those by various type houses who give them the same name and those modified by advertising agencies and designers. I've seen a couple of printed jobs refused by the client because the kerning was off by a molecule due to the incorrect version of a font being used.
This is something I would bet FontExplorer X can't do. As long as Times (example) is open, it would be happy. Quark, InDesign, or whichever program would also be happy if that's the font name it's looking for.
But, if it's a different version, or a modified font, you could be in deep doo doo.
I can't think of any professional shop around here that doesn't use Suitcase. It's ability to use the correct font every time, or at least warn you it's not available, is reason enough for me to use nothing else.