Recommend me an operating system!

[zottffssen]

I'm building a NAS/Media server/file storage/torrentbox computer next week. I'll start off with a single 3TB disk and eventually build up to 4 as I acquire money.

Here are my needs/wants:
- ZFS
- Can be run headless
- compatible with rtorrent/rutorrent (I specifically want to download 100% legal things and then have them auto extracted and moved to a folder)
- compatible with plex media server

I was thinking something like FreeNAS or ClearOS.

Any ideas would be appreciated.

[oclockforlyfe]

I've always thought that ClearOS was a small business server. In fact, I've never heard of it being used for a media server. I've heard of FreeNAS being used though.