Mac Mini to replace a NAS
I'm thinking of getting a Mac Mini (probably 2012 model) to run headless and use as a NAS/Plex media server/downloading machine. I'd probably repace the HDD with a smallish SSD to speed it up. Can this be done easily, and what alternatives should I consider?
At the moment I have a Lacie Network Space 2 as a DLNA server and Time Machine backup (for my MBP), but could this be done by the Mac Mini? Could any USB hard drives on the Mac be accessible by other computers on the network?
Most of the content I'd be watching is at least 720p, so at the moment I convert everything to MP4 before moving to the NAS. The Mac will be powerful enough to transcode HD media, so I wouldn't need to do this any more.
I'm also after a fairly power efficient solution if possible, so would it be possible to schedule the Mini to switch on/off at certain times of day, but also have some sort of remote 'wake on LAN' command if I needed to wake it at other times?
Is a Mac Mini overkill for what I need? Is there anything else I should be aware of? All help/advice appreciated!