Notes: my DAC does not use USB power, and the USB power is turned off at my server. Additionally, my server has a very low noise SOtM USB output card, powered by a dedicated shunt regulated super low noise power supply.
I have not tested a lot of USB cables, but the Nordost was defintely better than the Wireworld Starlight in my set up. The Nordost offered a more precise definition of leading edge transients, and tone, on really good recordings. The difference was most noticeable on a 24/192 download of Beethoven String Quartets from 2L. My feeling regarding USB cables (in my system noise is likely not a big problem for the USB cable to deal with) is that speed/bandwidth of the cable is the most important factor: so that the cable can transmit squarewaves as close to "perfect" as possible. Nordost's design, with an air dialectric makes sense in this context. And I also like that the Nordost cable is made in the US.