My two cents? The DAC is more important as that is where the data is converted into an analog signal. It's the spot where jitter, distortion, frequency non-linearity and noise can end up in the sound we hear. Until then, the streamer and all of the other devices upstream are simply handling data packets. Now, that's not to say that the streamer isn't important. RFI control can be done poorly, or well, for example. And, the streamer and its associated programming is where we interface to select music, build playlists, etc., so a poor design here can certainly leave us with negative thoughts that may affect our perception.