The answer heavily depends on your needs.
If you want to browse the server in Finder or your file manager of choice, you will need an app that can mount it into a folder, instead of just browsing it in the app itself.
If you make many small changes to the contents of a folder, but always need to have an authentic backup on the server, you need a sync-capable client.
If you work with large amounts of files and multiple versions of the same folder, side-by-side comparison is absolutely vital. Same goes for advanced, condition-based search.
Additional needs may arise, such as archive extraction or compression.