I did the switch from a Node 130 w/ upgraded power supply (which in itself was a great improvement) to a Lumin U1 w/ X1 power supply, and it's night and day improvement in every way. As it should be for the price difference. Better bass, sound stage, definition, detail, etc.
Personally, I find playing local FLAC vs the identical song on Qobuz does reveal slight differences. But neither are better or worse. Local files sound cleaner, more defined, and more detailed by a slight margin. However, that doesn't necessarily mean it's always more enjoyable. And even then, the differences are splitting hairs with this level of streamer.