For those that can perceive a difference in streamers & are curious as to why there is a very good YouTuber under the name Analogholic that has done a great video in layman's terms about streamers. He also has quite a few other topic videos that I feel are a great service to the audio community. Quite a few on the topic of digital.
As far as Nodes & their sound quality I think that the Nano is extremely good as a transport. It went well with my Pontus 15th & Laiv uDac. I think it even sounds pretty good with my more analytical RME dac. I have the Icon as well..& for transport duty I like the Nano better. You do have the option of adding an external PS with the Nano & you get an obvious improvement. To upgrade the ICON it will run you about $550 U.S. for the Teddy Pardo/Bluesound upgrade.
I also tried the budget WiiM Ultra a few months back. I was absolutely amazed with all the features the Ultra offers for that price. Very nice device. It just didn't mesh well in any of my systems as far as sound quality. Just meaning that it didn't sound as good to me as the other budget type streamers I had on hand (Zen Stream & Primare NP5) I'm not dissing the Ultra. Great device.
But yeah, the Nano is pretty smooth with a nice dark background as a transport. I used a Sbooster & Neotech NEVD-2001 Coaxial. Though when I first hooked up the Nano I used a cheap IFI PowerX that was powering a switch but ended up using Wifi with the Nano. Cheap powerX switch mode was a nice pairing.
I felt the ICON sounded best using its toslink output..but I haven't even tried the USB or Toslink on the Nano. I came across a used Nano for $200 a couple weeks & bought it just to check it out. I started with the coaxial output & I just haven't bothered to try the other outputs to yet.