Welcome to the thread. A number of users on this forum have experience with either the Synology or Netgear systems. The advantages of a NAS are they are usually small in footprint, comparatively speaking, and they usually enjoy very low power consumption. On the down side, they tend to be a bit more expensive than a roll-your-own, and unless you purchase a high-end model, expandability can be a real challenge.
I will take the time to enter into a little more lengthy discourse this evening, but in the mean time I request that you think a bit about your needs in terms of capacity and usage both now and in the near future, and let us know what they are. The answers will help determine a good path for you to follow. Note that you need to think about not only how much capacity you will need, but also what types of files ( video only or audiom photos, video, and perhaps general purpose files? MPEG-II? MKV? h.264? ), and what you will be doing with them (transferring to a handheld device? Burning to DVD?). It also encompasses how much you want to spend.