I managed to get my hands on a Synology DS209+II nas from work that was being thrown away and it's fantastic. I stuck a few TBs of space into it, it will put stuff out over Windows sharing, NFS, all sorts of technolgoeis. You can download addons for it for example, you can make it so a .torrent file in a particular directory, will start the NAS downlaoding that torrent, amongst other things.
Synology devices are pretty good for the consumer - we got rid of it because it wasn't quiote 'enterprise grade'.
I would say NAS all the way, They're not very expensive either, be sure to get one with at least 2 bays, so you can have it in RAID either for redundancy, no REAL advantage putting it in performance mode (RAID0 stripe) since it's a networked device anyway and will be subject to multiple things slowing it down on the way.