Well nothing prevents you from using the current build and just not using (or not even including) the batteries. It should be cheaper as well, particularly if you need to get panels made. If I'm reading it correctly--and I've been following--the improvements are supposed to be more about usability, like having jacks on the back side and a 1/4" jack, and eliminated turn on/off transients (though those are already pretty small), then anything to do with sound quality or which headphones can be driven. Also there's the ODAC option daughterboard for the desktop version, but supposedly that can just run standalone from USB power if you wanted that.
"Portable" or "transportable" doesn't mean it can't hang with many much larger desktop amps, or exceed them in some areas.