Using it as NAS device
If you were expecting the Netgear WNDR4700 to have the same type of comprehensive features as a true NAS, you will be disappointed. It's basically the same as any other Netgear router with a USB port. Readyshare already made it possible to access your files on an external hard disk via the cloud or ftp, and ReadyDLNA is also not a new feature. These options are also available with the WNDR4700, except that the files are then located on the internal disk.
The distinguishing factor of the WNDR4700 compared to other routers is the fact that it has a built-in back-up function. Netgear includes the ReadyShare Vault software for this, which you can create a back-up schedule with among other things.
The main function of the hard disk inside the WNDR4700 is for storing back-ups and for making your files available to devices outside of your network. If you only use a NAS for these things, then you could say that the WNDR4700 makes a NAS superfluous in your case. If you also like using a NAS for activities like downloading, you're much better off with an actual NAS. That's because it's not possible to install apps in the Netgear router, so you won't have the same type of features. Then again, Netgear also sells NAS devices, so in a way it wouldn't make sense if they created a router product that makes their own NAS devices obsolete.
We tested the performance of the WNDR4700. In NAS Performance Tester we arrived at a write speed of 37 MB/s and a read speed of 90 MB/s. Intel NAS PT registered an average transfer rate of 55 MB/s. Those speeds are pretty good, and batter than those of the Western Digital My Net 1TB/2TB, even if a high-end NAS is faster. But for making (incremental) back-ups is more than fast enough.
We measured the speed of the USB 3.0 ports by copying a 140 MB video files from a laptop connected via ethernet to an external SSD connected to the USB port. We arrived at 28 MB/s for writing and 70 MB/s for reading. We have not yet seen routers score this high, and these speeds are good enough to be useful for certain tasks. Many router's don't do better than 10-15 MB/s both ways. The WD My Net N900 that we tested a few months back gets the closest with 20 MB/s. It's striking that the performance isn't that different from that of the internal hard disk, and since you have two USB ports on the router, it makes the usefulness of the internal disk debatable. We were not able to test the transfer rates of both USB ports at the same time.