ND5 XS

I have ripped my entire CD collection using my UnitiServe SSD, the music is now stored on a Qnap NAS. Playback is by digital coaxial from the UnitiServe to my Supernait. 

I was thinking of getting rid of the UnitiServe, and getting the ND5 XS, which has a much better DAC, and Connecting it with an analogue cable to the Supernait.

Would this be a good upgrade, or pointless?

Any advice would be much appreciated.