Dunu asked me to not post impressions until the burn-in is done, and they adviced 200 hours of burn-in. I always respect companies advice.
So far, and I'm very early in the burn-in process, but Falcon-C comapred to DK-3001 has more of a V-shaped signature, with more treble and bass amounts. They also bring the details more forward, where DK-3001 is more relaxing. Those are early impressions without burn-in, but might be good to have so you know what to expect with burn-in as sonic changes go.
Now this won't change with burn-in, but the comfort is different. DK-3001 was maybe hit and miss with comfort? Well Falcon-C is an angelic IEM at the comfort level, it is so extremely ergonomic and well made, I didn't even need more than a second with the included spinfit tips, and even the tips that are not spinfit, Falcon-C just sits in your ears. It is really really well thought.
Now, Falcon-C leaks a bit of sound, but amazingly, while music is playing, they somehow isolate. My girl was shouting at me, and I didn't hear a thing while I was wearing Falcon-C today, but I do think they are open, from the design.
The cable is also really really nice. Like beautiful braided cable which looks and feels very high quality.