I'll have to research those too. mainly i'm looking into getting a zapco DAII-SL or a "Crystal CDB43122 evaluation board"
they both have coax in and balanced outputs. I have no hands on experience though :-\. the crystal has a very low output voltage (especially compared to the zapco units) but It's supposed to sound a warmer and richer then the zapco. The upside is taht i'm going into a phaze tube x-over that should up the voltage of the signals, and my tube amps don't really ask for a high voltage input.
New System in progress:
Phaze TD1500 ~> Dynaudio MD130
Phaze TD1500 ~> Seas g18rnx/p
Zapco Ref 500.1 ~ 12" tc-9
Behringer DCX2496 ~ Envision Electronics psu