I see that this discussion is really old and not solved yet, unfortunately.
Defraggler is really SLOW on my i7 950 3.00GHz, 24 GB RAM system.
HD is the Windows 7 x64 OS 1TB Seagate Barracuda, I would say enough fast, used 50%.
Defraggler is saying more than 1 (one?!) day to complete a QUICK DEFRAG...?! Quick. .. for a normal defrag I should park this computer and buy a new one to work in the meantime..?!
Do not understand really ... is the PRO version running faster!?