Although this application has some nice features it's way to expensive as all this is already build into the system for years. (Until Apple removed or complicated using some parts with their 10.4 'downgrade').

Just start learning to use the power of your shell. A simple 'cronjob' or 'at' together with 'find' could do much more for you. If you need space why not ask your shell to find all documents/files not used for time x and compress them. Or automaticly bzip2 and hide away your trash to remove it later. You can even start to create compressed applications that would still be useable while using half the space (realtime decompression into memory). It's all there for years and free.

So if you need a GUI or don't won't to learn anything new buy this application. Otherwise just learn what's already build into the system.