Something specific about the K271 sounds amazing to me. It's interesting what Superlux has done and I'd like to grab a model with similar signature to the K271 mk2 for comparisons sake, and disassembly/inspection. From innerfidelity's headphone graphs, the HD681 look almost the same as the K271 (smiley face is ok. It's the pattern in the highs that seems to matter for me):
Is it safe to say these will sound very similar? Is there a better choice?