API a2d? Brian uses one and could possible chime in.
I need the DA as well, in fact the DA is much more important since work wise I'm just mixing. I might just get something like a Benchmark DAC1 and hook it up to the firefaces digitial outs. It's just unfortunate because that will mean I'll have to wait longer since I was planning on selling my fireface to give me a little more buying power.
I like the look of the Duet, but honestly I absolutely hate the breakout box system. I'm not fussed about portability at all, its not going anywhere.
That being said, I think this might be a case of "if it ain't broke don't fix it," I'm not noticing my DA affecting my mixes. I don't go into other studios and suddenly notice how amazing the
conversion sounds. It's usually the sound of the control room coupled with fantastic acoustic treatment. I think I'm having a giant stress over the last 0.0000025%.
I think if I were mixing with outboard and dealing with a lot of loopbacks I'd be noticing the difference.
I think what might be a smarter decision for me is just to keep saving and move to something that will actually improve my workflow, like moving to a HD system on a better computer, and if my studio doesn't get to that stage it doesn't get there.