I came to a scenario to migrate the Box content to SharePoint (Office 365). The cost effective solution is the BOX site/folder owners can use the SharePoint Library Open with Explorer features to move the files from Box to SharePoint Online.
If you would like to automate the process for large content, there are many 3rd party Tools are available in market. I explored the skysync http://www.skysync.com/ which is very straight forward to migrate the content from Box to SharePoint or SharePoint to Box.
Skysync software can be used to Sync or Migrate Files between SharePoint, Box, Office 365, Huddle, Dropbox, Network File Systems & more!
Skysync software is available in 3 editions (Pro, Business and Enterprise) , prices and features are different is each model.
It is very easy to setup a new job for sync or migration. The details features can be find here.