I got this primarily to store and preserve my photos. I have it setup in Raid 1 to assure I don't lose my important stuff. Due to excess space I store a pretty decent movie/tv collection on it as well. My only problems with this product lie with the CPU capability, though this may just be Plex's fault for not properly supporting formats like MKV.
If your main intention for this device is to stream from Plex, I must warn you, it is very poor at handling MKV files and will typically: A) Lag consistently B) Refuse to even play, saying the server is not powerful enough.
Overall does everything I intended it to do, happy with my purchase.