I've just had another look at the websites for two of the programs we mentioned.

A difference I notice between the free multi platform photorec and the Windows only CardRecover is the file formats recovered.

CardRecover supports JPG JPEG TIF AVI MPG MOV MPEG ASF MP4 3GP MTS MP3 WAV and a number of raw photo formats.

PhotoRec supports over 300 and includes Office formats, archive formats, etc. as well as media ones. List here

At a quick look I think CardRecover probably supports more camera specific raw files. PhotoRec does provide a mechanism to add ones own custom formats though.