You might add the Lake People RS 06 to your list.
It's very clear and neutral, but has a strong and natural feel to the sound.
Here is how I found it: I started with the dac in my NAD C328 integrated amp into Wharfedale Denton speakers. I ran coaxial from my Audiolab 6000 cd transport and toslink from my Samsung tv.
After a while, a became a bit dissatisfied with the clarity and staging. I started my journey, trying the Topping D30, Schiit Modius, Project Pre Box S2 (which died within a week), ifi Zen, and Schiit Bifrost 2. None of them provided what I was looking for. The Schiit products and the Zen, although using different technologies, were rather dry for my taste. The Schiit Bifrost couldn't keep up with the dynamic swings in the classical music recordings I like, creating a muddied picture. The Topping was nice sounding, but was very cramped in staging. The Project had a very nice sound, but it was unreliable.
About the same time, I started looking for an external headphone amp. I wanted one with sufficient power to run my Beyerdynamic DT 880 (600 ohm) and DT 1990 (250 ohm) headphones, but preferably a discrete circuit unit for a more natural sound. I was being turned off of the Schiit units because of my dissatisfaction with their dacs, so I avoided their headphone amps. After research online, I decided to try the Lake People G111. And that turned out to be the perfect fit for my headphones: clear, powerful, and natural. Satisfied with that purchase, I decided to try their RS 06 dac. It too is very clear, natural, and provides very good soundstage. I sold off the Bifrost 2 and have been very satisfied with these units ever since. I listen daily with headphones and several times a week with speakers.
