I agree that their pro products are much better performers, notably the Delta 410 (which I currently use in my movie PC).
I think the only thing really holding the Revo back, however, is the somewhat immature drivers. They've got a house full of Mac driver programmers from what they say but Windows and specifically Direct X sound implementations are fairly new to them, I think they'll come along in due time. As for analog output, however, the one I've played with sounded every bit as good to my ears through my Klipsch speakers as the 410 I have.
But, on the related topic of low levels, meh, my PC has two sound settings, rattle the walls and off

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