thecus units were a better option over buffalo tripe. However, if you have an IT department that knows IT then openfiler is an even better option, especially as it supports iSCSI
Desktop and low-end rackmount NAS boxes keep on getting more powerful and Thecus has just introduced a brace of new ones, together with directly attached storage box that can be daisy-chained to a master unit. The rackmount N4510 and desktop N7510 are both Atom-powered, with 2GB of DDR3 SDRAM, and have 4- and 7-bays respectively …
All these NAS systems are overpriced!
Build your own for the same price and get 2-4 times more powerful..
Personally I brought a mini itx case, whacked in 4x2tb drive, 16gb ram and an i5 cpu, all for less than £500. It is OTT for just a NAS, so i run ESX on it. With a VM for a NAS, another for security, a sandbox for downloading etc.
My experience has been that at the price point the Thecus N8800pro for just less than £2000.00 is cheaper than we could manage building it ourselves.
it comes with 8 x 2TB drives (giving 11TB useable in Raid 5) and supports iSCSI, as well as all the usual protocols.
We use quite a few of them dotted around branch offices for backup storage.
(I am not employed by or otherwise associated with Thecus)