I agree with what you are saying but "far too often" the retail client forgets that most audio stores and audio distribution companies have had the opportunity to A/B many more pieces of equipment than any consumer will every hear. Personally we have A/B 76 different digital front ends.
Truth is if you want to get the absolute ultimate out of a Rockna dac, you need to run it i2S connection into the Rockna Wavedream Net. Again I know it sounds like sales but the Rockna streamer is the perfect match to the Rockna dacs. Also your i2S cable and Ethernet cable going to the Rockna Wavedream Net are super important. Every little detail makes a big difference, just like setting up a table properly.