I have been using DVD Shrink for some time but when it produced a cyclic redundancy error I thought I would download a trial of DVDFab6. What I found was that DVDFab was very slow. Eventually I decided to copy the main movie in the hope that it would be quicker. I started the process at 5pm and seven hours later (midnight) DVDFab was telling me that it was going to take another 35 hours. When I checked seven hours later (ie 7am) it was ready to burn.
As DVD Shrink takes about half an hour to copy and burn a DVD I assume DVDFab would normally take a similar time.