I was looking at the same choice a few months ago. I have a Holo Audio Spring3 KTE DAC and I've been using a Sony UBP-X800E 4K Bluray player to play SACD's and as a CD transport. I also have an Intel NUC as a Roon Core. I listen to a mix of LP's, CD's and stream from my NAS drive. I felt that CD's sounded better than streaming from the Roon core to the DAC so I wanted to get a streamer to improve the sound. From dealers I spoke to I was given the impression that the Aurender N200 was the better streamer with a more natural sound. I was told it would support Roon in the future. I liked the fact that the Lumin U2 supports fiber and Lumin says it has a USB interface that connects directly to the system. I was able to get the Lumin U2 for about $2K less than the list for the Aurender and the Aurender would have cost close to twice what my DAC cost, which I have been very happy with. I couldn't hear either, so I ended up going with the Lumin U2 for the lower price and the known Roon support. It definitely has been a significant upgrade in sound for streaming and I can use the Lumin app, which seems decent and also use Roon, which I own a lifetime license for. I think the Lumin app and Roon sound different, but I couldn't say one is definitively better. I especially like the Roon feature of viewing info about artists and albums, so I'm glad I haven't lost that. I would say that CD's sound different than streaming, and although I wouldn't say the streamer sounds definitively better than CD's, I would say they're on a more comparable level now. I'm still curious how the Aurender N200 would sound, and don't know if I made the best choice, but I am happy with the Lumin U2 and plan to try the fiber networking soon.