I have the Oppo BDP-103, but have a HTPC connected to it via HDMI and a Drobo FS Network Attached Storage Unit. I have not tried the network connection from the Drobo directly to the Oppo, but it works great through the HTPC for music and movies.
I think the advantages include large capacity (up to 15TB), ease of setup, redundancy, location flexibility via ethernet cable, and potential multi-room options.