In its latest version, this has become a superb program. Basically, it is a full-featured, rationally designed user interface for Spotlight searches. It can supplement what Apple provided or fully replace it. With the redesigned "Blitz Search" feature found in the latest version (an unfortunate name, I think!), which provides access from the menu bar, I have started using it as a full replacement for Apple's Spotlight interface, and I am very happy with it.

Support through the forums on the developer's website is first-rate as well.