Yeah that doesn't seem worth it even though we already hae Office 365 and therefore a subscription. MS' recommendation is to use Sharepoint for sharing between users and Onedrive for personal storage.

I'm looking at Dropbox but its permissions scheme is a bit wonky. Their version of a "team folder" gives everyone read access at a minimum and you can't override that with a "no access" permission for a group or anything. Also adding people to groups doesn't magically show folders that that group has access to.