There aren't that many streamer only devices with no DAC, so it's not easy to compare different streamers into the same DAC. What I have done is compared the sound of the Bluesound Node 2 with its internal DAC to using my Sony TA-ZH1ES headphone amp's DAC. There was a noticeable improvement using the DAC in the Sony. For my other Node 2, I used my Auralic Vega DAC instead of the Node 2's internal DAC. I never did a comparison between the Vega and the Node 2's DAC.
While that doesn't answer the question of using different streamers with the same DAC, it lays some groundwork for what I did next, which was to replace the Node 2/Vega combination with a TEAC NT-505 streamer/DAC. The TEAC, which cost less than $2,000 easily bested the sound quality of the Node 2 into the Vega (which was a $3,500 DAC when new).
While it's possible that the Vega just isn't that good, or that the DAC in the TEAC is a giant killer, I believe that the difference is more likely due to having better streaming hardware sending the signal to the DAC. I can't think of much, if anything, in the audio chain that doesn't matter, so it stands to reason that a better streaming source will result in better sound quality.
I would be very interested in a technical explanation of what it is that makes one streamer produce better sound than another.