Macintosh dac-1.

There's certainly a space and convenience factor with the internal DAC - without knowing your system my opinion is not very informed.

And I would be more inclined to explore an external DAC.

I used to own C2600 which includes Mc's internal DAC.  It was better than my Node2i's DAC but it didn't hold a candle to the Moon 280D (DAC + Streamer) when I upgraded from the Node 2i.

Call Audio Classics and ask their opinion, they won't steer you wrong, or BS you.  The DAC 1 in my C2500 is fine for what I use it for, but I am not really a fan of the Sabre DAC.