The Schiit website was quite critical of USB before they updated the USB board. They said it was like "telling a chef to make a great meal but he could only use McDonalds hamburgers" or something like that. All that talk has been removed, so they must think the new board is quite a step up over the old one.
If you have an optical or coax out on your source I would pass on the USB though.
I think this USB board should much better than the old one.
Jason mentioned on an email that optical is usually better than USB.
But that "better" is most likely barely noticeable.