I am going from a Cambridge 840C to the just released 752BD Blu-ray player with accessible DAC.
But only because I own some SACD's and DVD Audio disks and wish to play them.
Otherwise I would keep the 840C, it is an incredible machine.
Review don't tell all of course, but it seems the NAD unit falls a bit short.
http://www.whathifi.com/Review/NAD-C565BEE/