Lunar,
Both arrays are JBOD (no redundancy), but are in seperate locations with scheduled backups between. This is plenty reliable for anything shy of a datacenter IMHO (no single point of failure).
Bozo,
I like quiet computers. Not just quiet when idle, but quiet full-stop. Therefore temperature controlled fans get me nowhere. I'd much rather have the quietest fans I can get, then control them myself down to an inaudible level and leave them there. If they are unable to keep my load cool when spinning at that speed, I designed something wrong.