Every version we have used has failed in one way or another. Most recently, when I set up Source and Destination HDs and select what to back up, it garbles things badly, especially by refusing to back up to the external HD I have picked and switching to another HD. Worse, it saves to the wrong backup folder.
As with another reviewer, when I tried to recover, it was not effective.
I know that Apple is capable of superior software design, as with OS X, but the .Mac "benefits" package software has been second rate at best.