ClassicalViola, actually I won't be A/Bing them. I listen to both enough every week (on a variety of sources such as the X3, DX50, and iPod Classics) to know the differences in sound signatures. Both iems are good, but the H3 is great to my ears. The sound signatures aren't anything alike to even compare, and the technology is used differently in both. Let me explain further.
The DN-1000 uses it's dynamic driver mainly for the bass, and then one BA covers the mid and the other one the highs (I'm sure there may be some crossfeed among drivers, but I don't know how much or where). The H3, on the other hand, use its 16mm dynamic driver as a full woofer (similar to how speakers are set up with a woofer and tweeter), but it also uses one of its BA driver full-range too. Finally, the other BA is used only as a super-tweeter. This is why I disagree with djvkool about the DN-1000 being just as good or better than the H3. Technically they don't even compare.
So I find the H3, as I stated on another thread, as sounding almost like a headphone in my ear. The DN-1000, on the other hand, sounds like a very detailed iem. The frequencies in the DN-1000, however, don't extend in detail at all like the frequencies do in the H3 (on either end). The H3 has a clearly fuller, taller, livelier, and more 3-Dish sound than the DN-1000. The Sony has a wider soundstage, greater headstage, and depth between instruments. It has more space between instruments and vocals. And it's not subtle. It kicks you in the face, the differences between the H3 and the DN-1000. Now why djvkool didn't hear these differences I don't know, but I can only speculate that he didn't have good seal with the H3 when he did his brief audition.
But to my ears, that price difference is there for a reason. The DN-1000 doesn't compete with the H3, but the Dunu is a very good earphone. I would not consider the DN-1000 a high-resolution earphone, but the H3 definitely is. I hope that helps.