I had a node 2 before upgrading to a MK2 Zenith and for me, the Zenith is noticeably superior (as it should be I guess considering the price difference!).
Just be carefull as we are not comparing apples with, er apples.
The node has a built in dac. It should be capable of streaming music from Spotify, qobuz and local NAS. The Zenith does not have an in built dac, from memory.
There is also a price difference. And watch the software that drives each too.
The Zen Mini does have a built in DAC and is probably the closest to the Node performance wise. I’ve heard the Node and the Mini using the same DAC. The Mini by a clear distance for me.
I can’t comment on the Innuos server but I have a Node 2i doing streaming duties at the moment. As a stand-alone device using the inbuilt dac and wi-fi I’d say it was pretty average and nothing to write home about. However, connected to a decent dac, hardwired with good ethernet cable, using an EE 8 switch and streaming Qobuz it’s a whole different kettle of fish. I’ve been very impressed with the performance and has me questioning why I’d spend much more money? It’s never going to sound better than my CD555 or my LP12 but what it does do it does very well and allows me to access music I might never otherwise hear.