Fairly good notes from Claus in three posts on p.8 of the tir na hifi thread. Claus heard it as 'much better' compared directly with the JKDAC - the earlier, ESS Sabre-based one, not the JKDAC32.
Audirvana-plus "in integer/direct mode" had quite a lot to do with the noticed improvement. Comments are hard to interpret in places; e.g. in Claus' third post can't tell whether Audirvana was used with the JKDAC as well.
Still, some promising notes (more natural, leaner with less bloat, refined, 'calmer' [?] soundstage, "shocked to hear things I had never heard before", "a worthwhile upgrade").
Added to Tony's contribution on p.4, that's two sets of comparison-based impressions in favor of Ciunas.