The DMC-1 is based on the Grand Theater IV, designed by Sunfire (Carver's company) - I came across an older review for the Theater III that suggested that Carver's design role was more secondary, so I don't know how much of the nitty-gritty he did on it. The Grand IV/DMC-1 is a very nice piece of gear, although the 990 actually compares very well to it. I've heard folks who preferred the DMC-1 (although typically by only a narrow margin) and other folks who preferred the 990 for its greater neutrality. As psyprof points out, the 990 is consistently praised for its music performance. Music performance is an excellent litmus test for overall performance.

As psyprof indicates, compressed audio formats like MP3 are about the bottom of the ladder for fidelity among digital audio formats - below the CD and MiniDisc and well below SACD and DVD-Audio. Does that mean they are to be disregarded? No, they can and do have their place. But it's worth pointing out that if MP3 sounds good, those other formats can and will sound even better.