I recently purchased a Hegel H300 integrated amp and did an a/b comparison between its internal DAC with my NAD M50 feeding it and my Ayre C5xe into the Hegel's balanced inputs. The Hegel's internal DAC did some things better (pace and imaging) and the Ayre did some things better (dynamics and a more forward presence). In the end, I settled for the Hegel internal DAC.
My understanding is that all of Hegel's DACs whether stand alone units or internal units are unique. For instance, the internal DAC in the Hegel H70 integrated amp is not the same as the HD11 stand alone DAC as one dealer has claimed (the H70s DAC may be inferior to the HD11 but at $2,100 the H70 is a great value even if the internal DAC is not utilized). Similarly, the H300's internal DAC is neither the stand alone HD20 nor the HD25. In terms of quality it probably lies somewhere in between those two stand alone units.
My understanding is that all of Hegel's DACs whether stand alone units or internal units are unique. For instance, the internal DAC in the Hegel H70 integrated amp is not the same as the HD11 stand alone DAC as one dealer has claimed (the H70s DAC may be inferior to the HD11 but at $2,100 the H70 is a great value even if the internal DAC is not utilized). Similarly, the H300's internal DAC is neither the stand alone HD20 nor the HD25. In terms of quality it probably lies somewhere in between those two stand alone units.