We've been using 2 Buffalo LinkStations of 320Gb each for shared directory and employee's server storage (around 20 employees). So only documents (word, excel, cad drawings etc.) and database backup of the main application server (ERP, Accounting) 1 buffalo box serves as a main one, located at the server room, next to the main application server and the other buffalo box is located on the opposite side of the building (for fire protection) in a secure storage room and backs up the first one. We also have several external HDs that backs up everything from the buffalo box for an offsite backup.

After 3.5 years of using these, capacity is a main limitation, I'm planning a replacement and would like to use FreeNAS (we already use monowall with great success). I would like to keep it simple and continue similar setup, building two low power boxes with 1 hd (2Tb) each. Is low power atom mobo OK? Not sure about HDs? I've read on this site somebody mentioning more seagate ES2 as more reliable and better performing. How would those eco/green drives compare. We've been pretty happy with speed of Buffalo boxes and I don't want my users to notice any slowdown.

Any suggestion?