NAS transfer rates are always tough to measure. Depending on your router or switch, your hard drive and the system you're accessing the files with, the rates you see are bound to vary. That said, we did our best to test the drive out in a variety of scenarios (wired via router, wired directly via Ethernet and wireless via router) and with both a Mac and PC. We also tested transfers remotely over the Internet.
When using a 1,012.8MB .dmg file, we calculated a write rate of 23.44MB/sec and a read rate of 22.02MB/sec, which are strong numbers. Just to put things in perspective, the Maxtor Central Axis Business Edition NAS Server that we lauded back in March notched large file transfer rates of around half of these speeds. The Western Digital My Book World Edition NAS device saw write rates that were significantly slower but read rates that were marginally higher. Like we stated earlier, it's tough to compare results with different test setups, but as a general guide, we can see that QNAP's TS-119 holds its own amongst the competition. When transferring a folder full of JPEG images amounting to around 383MB, we saw performance drop somewhat as expected. Still, results were quite pleasing at 18.9MB/sec (write) and 17.1MB/sec (read).
We should note that downloading and uploading files over Wi-Fi was significantly less speedy (around 30% less in our testing) than the transfers from machines connected over Ethernet. Still, for a NAS device, we were really pleased with the performance. The Web interface was generally quick to load, and files / folders were quick to pop up in Windows Explorer when called upon. Even when accessing the drive remotely over the Internet -- which is far and away the slowest way to go -- we found the UI to be remarkably responsive.
It's hard to quantify things such as "snappiness" and "responsiveness," but suffice it to say, we couldn't be happier with the overall experience. QNAP has ensured that lag is kept to a minimum, and in all but a few circumstances, we felt more like we were interacting with a locally connected external HDD than a NAS drive. For anyone who has had to deal with sluggish NAS interfaces of the past, you'll fully understand just how impressive this is. Indeed, we sorely wish that all NAS interfaces could be this hasty.