Backup and Redundancy setup are 2 separate stuff.
If you want to archive your picture,
then Backup is the more idea solution.[...]
So is backup and archiving - their are different in scope and technology. Although, here for images it's less critical than for business data. Backup is to restore the working data in the shortest period of time. Archiving is the long-term storing over multiple years, preserving the files for future usage. Here, also the necessary software (binaries) must be considered. If one of the camera makers decides to abandon a certain file format then the last version of the respective program must be included in the archiving. Alternatively one can use file formats without a specific binding to a certain software / camera maker, e.g. DNG. Open formats have a much greater chance to be supported in long terms.