Why would you want that nightmare for something as simple as a home media server?
First, it runs its own proprietary operating system, so your chance of ever getting unpaid help if there is a problem is about zero.
Two, I believe it only supports NFS and not SMB. Many media streamers do support NFS, but not all, and some not well. Since it is a proprietary OS, who knows what support can be added.
Three, it uses storage blades and not just individual hard drives. When one of those blades eventually fails, can you find a used one for cheap? A new one may cost you $2000-$4000.
Four, for what it costs used, you can get 40 GB of storage elsewhere for half the price.