The DN2k is great, it is just very tip and source dependent like most IEMs. The micro detail is there, but the subbass rumble and boost people love is not. Luckily, the dn2k takes bass boost quite well and doesn't bleed it. This should be expected however, as Dunu advertises it on the package as "neutral", and for the most part it is.
I'm currently using the medium double flange that it came with, no spacer. Only had it on for a few hours, so I have many combos to go. The stock default tip didn't fit me well.
So far it is better than the KC06A in everything but bass impact, but not $200+ better. Diminishing returns. I really like it though.
Soundstage is also tip dependent.