I just ordered a pair for a small media room. I agree not sure why you would use a different external DAC, but I was told that if you need more room correction than is on board the Kii, then you may want to use an external DSP for full room correction. Hoping it is not needed, but they do have to go close to the back wall, so we'll see.

Studio System: UltraDAC, Analog Speakers, QNAP IS-453S Pro
Theater: Trinnov, 8kSPE, 4 5.2kSE, 7.2HCSE, Analog subs, DSP8000SEs
Roon (running headless on QNAP)