I had a DX300 with the original amp card, and it was a warmer, thicker presentation than I expected from iBasso (but very fast operation, and full play store for trying differnt music playback apps. It was a nice comfortable get l;ost in the music kind of experience. Now I have one with the newer stock amp card, and it is much more iBasso-y, in terms of sharp leading edges, resolution, and less warmth/thickness to the sound. It is good, but no match for my SP2000cu (which does the whole 'resolution thing' more authentically and convincingly (to my ears).
The L&P p6Pro does the non-digital sounding digital thing waaay good, and the Lottoo PAW6000 does the neutral thing quite well - which kind'a puts the squeeze on the DX300 in some ways. (I have a Cayin N6ii as well, and am pondering the r1 module-whereas a month ago i was pondering selliing it. (Such are the best-laid plans of audiophiles).
And yet there is the M8 (which I have not heard yet). Wondering what it would bring to my table, in particular, and what it would allow me to let go of, without a second thought.