This search started as a need to find a smaller DAC and streamer due to overcrowding in my cabinet. Current players Bricasti M3 and M5. But as I started looking and listening, I realized there is a sonic search as well; just to complicate the process. As much as I like the Bricasti gear, I have always yearned for a softer- perhaps more tube/ analogue sound.
op
since mid 2020 i have tried over 40 dacs in my system (now nearing 50), at various cost levels, learned a ton in the process as i have committed to streaming music in my system going forward
please check out my past posts answering varying queries like this on dac recommendations
of the ones you listed i have only had/heard a minority - here are my takeaways
-- border patrol... smooth, rolled off $1000 dac, mediocre overall, with a below average level of insight, air, or drive, probably one of the weakest on your list
-- audio mirror tubador ... i had the 3se, one gen prior to vlad’s latest, which i am sure has improved incrementally... a nice sounding dac, sweet rich and analog sounding, but had some issues with sibilance in my system, overall a fairly good value used at ~2000
-- audio note kit 4.1 - very nice sounding, lively yet rich, dynamic, holographic... but lots of tubes inside, truly gargantuan box, input card has limitations (only up to 96k sampling rate), if you can stand a refrigerator sized dac with zero features the sound is unimpeachable
-- i also had a bricasti m1 se mdx and i concur it is a truly excellent clean modern sounding dac, tonally accurate very precise open airy sounding but not overtly warm/rich in presentation per se (i liked the linear 2 filter setting best iirc)
for what sonics you seek, as you describe it i would suggest
-- denafrips pontus (rich tone, good detail and air, very slight grain, but still very very nice), for 1500
-- cambridge cxn v2 modded by modwright with tube output stage - beautiful sound, sweet yet dynamic, quite well focused, lovely tube magic at play here, nla modded new due to parts issues, but they do appear used occasionally
-- mhdt r2r tube buffered dac with upgraded tubes (we 2c51, or old stock 6dj8 via tube adapter) -- 80-85% of the modded cambridge but half the $$
-- msb analog dac with power base (lovely sounding, very appropriately named) - uber refined sweet treble yet at the same time airy open holographic good focus... $$$ but worth it, newer even more expensive msb’s are more modern precise sounding, which i do not prefer
i currently own and enjoy all of these mentioned, among a few others with a more ’modern’ sound