Do not underestimate the importance of long break-in time.
I've been surprised by the improvement in the TDSS-modified IDA-16 at more or less 300 hours after my getting it back from Bob.
The noise-floor in the standard IDA-16 is very low, but this very long break-in of the TDSS modification has made me quite literally sit-up and take note of the difference in the sheer realism of finely nuanced detail, most especially in vocal inflection, where I go: Oh, that's what she meant! ---All of which means, I think, that the noise-floor must be even lower.
Tom