This is the update to the Dac3 that allows for high rez playback.  Its a lot steeper than I thought it would be.  Still, I'm tempted.  I think someone on the Computer Audiophile forums was going on about how it uses a better USB chip too.  (as opposed to what the Dac3 uses) 
 
I'd have to get an explanation as to what it does better than the M Audio transit via toslink before buying.   
 
Someone talk me out of it.