888s apparently do work standalone, but sound terrible.
I used to work at a studio where we used an 882 for extra inputs (otherwise we had Digi192 and Apogee Rosettas), so I understand the concept. It worked in a pinch, but really, every $100 interface sounds better than those converters these days (and the 882 is actually only 20bit!)
Or do you want the sound of old, not-very-good converters?