The DigiOne or Usbridge may make a difference if you've got a badly designed DAC that's sensitive to jitter in spdif signals or to noise in USB power lines, but a properly designed modern DAC won't be sensitive to either. If you have a look at the
Modi 2 review you'll see why Allo picked that one to demonstrate the benefits of the Usbridge - the Modi 2 is sensitive to USB noise like no other DAC tested so far, and gets called out for it. You'll see no such sensitivity on the SU-8 v2 review, so no reason for a Usbridge. SPDIF jitter sensitivity is similarly a solved problem for most DACs now, with the occasional counterexample to show why it's still worth testing.