Very interesting, thanks for posting.
Obvious question would be why not swap over the power supplies and see if that edges the Boss even further ahead? Then you might see whether it would be worth upgrading the PS?
I am also thinking about upgrading PS, and am considering the IFI ipower 5v. Have you seen this:
https://www.computeraudiophile.com/f...-lps-and-smps/
I am using latest Moode with advanced RT kernal and upsample to 32/384, though I haven't done any comparisons with other settings to see the difference - sounds good to me!