QNAP, along with Synology, has carved out a little niche when it comes to making prosumer storage devices.
The TS-879 follows the same design language as pretty much everything else in QNAP's stable, offering eight drive bays with new secure clasps. Those who are security conscious should note that individual bays are not lockable by key, nor is any sort of fascia.
A status display is present on the front, as is a USB 2.0 port, a copy button (that the user can set to automatically copy into a folder on the NAS, or from the NAS into a set folder on the USB drive) and the power button. Apart from status lights on both the device and individual drives, the front is kept minimal, but it still gives you all the information you'll need.
Flip to the back, and you have VGA and HDMI outputs for diagnostics, four USB 2.0 ports, one USB 3.0 port, two eSATA ports and two gigabit Ethernet ports.
QNAP's UI is still good, managing to fit a huge number of features into a reasonably coherent interface. It seems that we're losing our battle to get the NAS vendors to remove the pointless application chooser when you load the web interface — from here, you can choose whether to go into NAS administration or other modules, like the web file manager.
The administration page is displayed with a tree view down the left, and a main pane on the right. As usual, the thing is packed with more features than should really be contained in a couple of paragraphs, but beggars can't be choosers.