Just be aware that it is a 2Tb / 4TB drive, information from the Western Digital website.
Double-safe backup with RAID 1 technology.
Set this system to data protection mode (also known as mirrored mode or RAID 1) and the capacity is divided in half. Half of the capacity is used to store your data and the other half is used for a duplicate copy. In the unlikely event that one drive fails, your data is protected because it's duplicated on the other drive.
Out of the box, this two-drive system combines both drives into one large volume, serving as one drive for maximum capacity.
What this means is that as a 2TB drive Your data in mirrored on both drives for better safety.
It also means that used as a 4Tb drive if either drive goes bad then everything is lost. To me this unacceptable.
You also find that it is a bit slow over the network. I had older WD NAS's ans they were not a ball of fire. I have since switched to Qnap TS-220 NAS's with Western Digital WD Red drives, They seem faster to me. I bought on sale with the 2 Red drives. To me one advantage is I can upgrade the drives to larger drives and not lose anything. The WD Red drive is a NAS rated drive FWIW. The Qnap's I use have USB 3.0 ports that are also included for high speed data backup to external drives.
Here is a link to Assorted driveless NAS's.
If You decide to go this route? The faster the processor in the NAS in general the better the performance will be.
Edited by rotor123, 24 February 2014 - 04:37 PM.