Hello,
I have played with several types of DACs. It depends on your system. Right now I am playing with an older R2R Electrocompaniet DAC. R2R has a more subdued sound, but better separation. The Denifrips is a winner. I like how they doubled the transformers and put them in a cabinet underneath. I have heard good things about the holo, but only the top model. The M2Tech sounds really nice but not warm like a tube at all. What I have noticed is under $5000 you get what you pay for. I prefer a separate power supply but I believe Denifrips handled that very well.
I have played with several types of DACs. It depends on your system. Right now I am playing with an older R2R Electrocompaniet DAC. R2R has a more subdued sound, but better separation. The Denifrips is a winner. I like how they doubled the transformers and put them in a cabinet underneath. I have heard good things about the holo, but only the top model. The M2Tech sounds really nice but not warm like a tube at all. What I have noticed is under $5000 you get what you pay for. I prefer a separate power supply but I believe Denifrips handled that very well.