I spent a week with the Bartok and owned the Bricasti for a while. Haven't heard the Esoteric.
At the same time I had the Nagra Tube DAC and a Matrix X Sabre 3. I have also owned the Chord DAVE/M Scaler and a number of others.
I kept the demo Bartok for a week but knew within minutes it would be returned to the store. Very impressive sound, big, deep and quite realistic sounding. But a little colourless, a little slow, and a bit too smooth. I found it lacked dynamics and excitement where the music called for it, and was ultimately not particularly engaging. It was great hi fi but, to use a term that many people hate, I did not find it "musical".
The Meitner is much cheaper, and I found it better than the DCS. Better dynamics, no irritating artifacts (as the Chord DAVE had), but over time there was something about it that didn't quite gel with me. Tonally it was a little on the lighter side, and there was a slightly "processed" quality to the sound. I initially was very impressed with it, but over time I liked it increasingly less and eventually sold it. However, between the Meitner and the Bartok, I would unhesitatingly choose the Meitner.
But as I mentioned above, around the same time I had bought the Matrix X Sabre 3, which is much less expensive than any of the other DACs I have mentioned, although still not "cheap". I'm sure you could see where this is heading, but I much preferred the Matrix DAC. After a year or so, I still have it and am very happy with it. To my ears it does nothing wrong, has no irritating artificacts, has a natural sense of dynamics and tonal colour, and is very engaging and non-fatiguing.
Obviously, this is all down to personal preference, so take it with a grain of salt since everyone hears these things differently.