Electrocompaniet DAC 1 + Interface or DAC 2

I have the Electrocompaniet system - Pre, 2 Powers and Nordost cables.
Using a Mac Mini as Transport, what of the 2 options.
1. The DAC ECD 1(without USB input) + Interface
2. The DAC ECD 2(with it)
Thank you
Which way did you go? I also have a Mac mini and  an EMC1up that I'm considering replacing with one of the ECD dacs.