I did look at FileBrowser and it's a pretty neat piece of software (and integrates really well with the document picker), but I don't really want to be creating files that live only on my iPad and for us, OneDrive For Business and SharePoint have become our corporate network storage (backed up locally and remotely before anyone says anything about trusting documents to the cloud)
I use FileBrowser... I just like the flexibility it has with using various cloud services.
It also uses SplitView.