I really like Synology DSM S.O. - but I am now seriously looking at QNap. Why?
Because of the HUGE difference in hardware spec. Yes, I will end up paying significantly more ... but for more power.
Looking at a DS415+ or a 1515+ but given they use the same processor, which according to folks who have a 415+ and have tested it is incapable of transcoding 1080p on the fly at higher bitrates (something Synology themselves have confirmed with their literature) I don't see that they are really applicable for home power-users.
Plus they don't have an HDMI port either (you have to buy the somewhat for play that...).
Now look at the QNap models - Quad core celeron 2.4Ghz up to i3 3.3Ghz processors, 2-16Gb RAM, HDMI port and capable of transcoding multiple streams simultaneously.... more money, sure - but it's more future-proof and has the potential for a LOT more memory , user-upgradable.
Some users have upgraded their x70's with i7 processors and 16Gb of RAM for a VERY fast NAS.
I'm not trying to bash Synology - far from it, they build high-quality products - but they seem to be stuck with the mindset that home users crave quiet, power-efficient devices
BUT they seem willing to sacrifice horsepower under the hood to give us what ???
That's an area where QNap seems to be targetting more effectively.
and a comparation table: