Daminion very flexible:
 allows to import all sorts of files: text files (like PDF), pictures, sound bits, movies... and retrieve them selecting whatever search option is convenient: import date, file type, keywords (tags)...
 a number of preset tags are useful, but Daminion allows user-defined tags too, which is helpful, in my case, to search e.g. for key topics, historical events, and animal species.
 support is very good: very responsive and helpful suggestions. I really appreciate the good communication. You're communicating with a human, not a system.
 it's small: the catalogue is just an 'umbrella', a file that remains fairly small (Mb's) and I can still access the files through a File Explorer. Daminion does not modify the original files. Review collected by and hosted on G2.com.