I confess I am relatively new to making DVD back ups...I bought my external LaCie d2 DVD U&I drive on Friday afternoon and was creating my own movie backups on Friday evening. The folks at dvdbackup, also a great and bug free product, mentioned your product in their literature and the rest is history.
I have a Mac G4/450, OS 10.2.6. Its not the newest G4 but does the trick quite nicely. DVD2oneX works flawlessly... so to anyone in the Mac community pondering stability of the product prior to purchase..worry not!