I too purchased File Scavanager and think I've gotten my money back several times over. It has recovered content from crashed drives, reformatted memory cards, etc.
One quirk I've noticed though is that Canon Raw (.CR2) files recovered from a formatted card show up with a .TIF extension. The file size is about right (21MB), and LightRoom seeems to be able to recover them, but it does seem a bit weird that the extension is off. Maybe it's guessing an extension in these cases?