I've been using Owncloud for a year now. One of my co-worker gave me his Pentium-4 IBM desktop from 2002, I installed Ubuntu server 12.04 and Owncloud server. I have a client running on my Android phone backing up all the pictures to the Owncloud server as well as desktop clients syncing folders. I also share pictures folders with my family and friends.
Owncloud came a long way and it has tons of apps. One of them i like is adding an external drive. This will allow the user not only add external hard drives but also internal folders, in case you decided to add 2nd hard drives. Also you can make owncloud secure by adding https / ssl.
Adding a 2nd hard drive to Owncloud server
