Version 1.4 has dramatically improved its capability, from a 2-star performer to a 5-star TOUR-DE-FORCE.Truly the best dragger of individual files and the whole drive. It is suggested that yo first defragment all of the individual files, and make sure that at least 15% of total disk space is free to begin. Then defrag the whole drive, and it will also do so for the free space.
I highly recommend that before beginning, you completely clean all junk, especially by using CCleaner or such.
Don't really know if it is doing anything...it's free though
A good software on the paper, but so long to defrag !!!