I'm still weighing up my options. The Thecus 5200 looks good on paper but doesn't seem to reliably do what it says on the tin .. yet. I looked at the ReadyNAS but that doesn't give the RAID6 option I was looking for. Does anyone have any experience of QSAN devices? The one I am looking at as an alternative to going with the unreliable 5200 is the QSAN S50E10 with 5x500Gb Hitachi SATA2 drives.
strata, I also think that Thecus' NAS devices need to mature their software a quite a bit more (still happy with my N5200 though), but I wouldn't expect Qsan to be the rock solid NAS of choice with their initial offerings either. Hard to evaluate a yet to be released product though.
The S50E10's enclosure looks like the one here: www.addonics.com/products/raid_system/ast4.asp ..with the top bay holding the Qsan unique part forming the brains of the NAS. Reminds me of a similar "IceCube" SFF PC I had a few years back - nice enough form factor but not as slim as the N5200.
You can always use FreeNAS, ClarkConnect or Ubuntui to "roll your own" NAS, maybe even using VNC to provide a richer than web access to your NAS. I have my N5200 back-up to my older Windows PC myself.