An excellent feature offered by the Duo, and common to many Buffalo NAS devices, is WebAccess. Ostensibly this just allows files on the Duo to be browsed via a compatible web browser, including Android's or mobile Safari. Where Buffalo excels is by offering its own dynamic DNS portal, such that you don't need to register with a third-party service in order to gain entry to your NAS remotely - it's a small touch, but a neat one.
It’s a system simple enough that most users shouldn't have any problems, without verging as close to patronising its users as the Netgear Stora. Further, while the feature set isn't quite as rich as the QNAP TS-219, nor the UI quite as snazzy, this is reflected in the £100-odd lower price.
The QNAP NAS, for example, offers three USB ports and can have a webcam connected to it. Conversely, the only function the Duo's USB port can serve - other than accommodating USB storage - is to hook up a USB printer, which can then be shared over a local network.
Also good is the bundled Memeo AutoBackup software. As you might guess, this backs up your data automatically. What's particularly noteworthy here is the smart placement of files into appropriate folders, saving you the effort. It's not flawless - if you're particular about how your files are arranged this isn't for you - but it's a damn sight better than performing the same process manually. If you're a Mac user, Time Machine support will be good news.
Other NAS devices offer more functionality - Netgear's ReadyNAS range supports third-party plugins, for example - but for a little under £200 you can't expect such luxuries. Those features the LinkStation Duo does offer work without any problems. What more can we ask for?
The feature set and performance of the Buffalo LinkStation Duo are hard to snub, especially given its reasonable asking price.