Attempting an upgrade to OS 10..5.8 on a G4 Powerbook, software update reported a lack of space. I therefore set Drive Genius to look for unwanted localisations and unneeded universal binaries and cache and temporary files and went to bed. The next morning the drive was dead and proved irrecoverable by Disk Utility and Disk Warrior which could not even see the Partition. I can only presume that DG drove the hard drive into the ground with its scanning. This was not a new machine but the HD failure at this time was too much of coincidence for me. A most unfortunate and expensive outcome from the first attempt at using this costly software. I would not recommend.