What matters for a network attached storage (NAS) devices? First, a well-implemented NAS has to focus on redundancy, performance or throughput. But beyond that, the best NAS devices are easy to use, reliable and well-cooled. These features come together to ensure that you have maximum uptime for accessing your important media and files over a local area network. In addition to the centralized computer storage, many NAS devices feature multiple hard drive bays, RAID support for physical disk redundancy or via duplication within Windows Home Server.
The following networked attached storage devices top our list of the best NAS devices you can buy.

QNAP Turbo NAS TS-809 Pro Network Storage Server - $1,669

No one ever said that a premium NAS would be cheap. With a price tag creeping towards $2,000, the QNAP Turbo NAS TS-809 Pro Network Storage Server is undeniably top of the line. And you get what you pay for. It packs eight bays for hard drives, RAID 0/5/5EE/6 support, iSCSI, web GUI for remote management, online capacity expansion and a nice status LCD on the front for when you want to get a snapshot without accessing it remotely.
In terms of hardware, the QNAP Turbo NAS TS-809 Pro has a Core 2 Duo processor with 2GB of DDR2-667 RAM and dual gigabit ports (handy for those without switches or anyone who might want to use failover as a redundant measure addressing network uptime).
If there’s a downside to this NAS device, it’s the lack of support for eSATA, which seriously hampers your compatibility for direct attached storage. You can still use a USB connection, but as you know, eSATA is much faster.
Overall, the TS-809 Pro is perfect for businesses who plan on serving their data with the utmost in reliability and redundancy.

Thecus N7700 Network Attached Storage Server - $800

At a lower price point than the QNAP TS-809, this Thecus model still packs plenty of potential. With seven hot-swap bays (one less than the TS-809), support for iSCSI, SMB/AFP/NFS (simultaneously) and multiple RAID volumes across different hard drives, the Thecus N7700 is fairly flexible. It’s dual Intel WG82574L and 70 Mb/s keep data moving quickly. Downside of this model: it’s fairly noisy (which may be a non-issue if you keep it in a separate room) and its web interface is a bit clunky, though definitely functional.

QNAP TS-509 Pro Network Attached Storage - $900

Three rungs down the ladder from the TS-809 and about $800 cheaper, the QNAP TS-509 has five bays and a network data transfer rate of 125. Beyond the lesser amount of bays, the TS-509 may be a better option if you plan on expanding it yourself. It supports iSCSI, has upgradeable RAM, has a VGA port for local access and can connect to hard drives via eSATA and USB. Like the TS-809, the TS-509 has dual gigabit Ethernet and a wide range of RAID flexibility.