What kind of performance are you after? If you're not after anything over 40MB/S, I'd go for unRAID. I use this at home and it's brilliant. I've replaced many drives over the years, and I've had two hard drives fail with no massive consequences (data isn't striped).
Plus, many many plugins are now available. SimpleFeatures (replacement gui), Plex Media Server, SQL, Email notifications with APCUPSD support etc etc.