First I'd like to thank you for the Tidal and Qobuz integration efforts. Access to HiRes streaming services takes the Volumio experince to a whole new level.
I've tested both MyVolumio plugins, and opted for Qobuz, since the Tidal plug-in does not do unfolding of the MQA encoded tracks, limiting playback to 44.1/48 kHz, if you do not have an MQA-enabled DAC. The HiRes Qobuz tracks, on the other hand, are rendered on my DAC in their full 96 kHz glory.
The search in the Qobuz plugin (version 2.502) is, however, not retrieving nearly all the tracks that I can stream on my Sublime+ account using the Qobuz Windows app. In fact, I have been unable to retrieve a single album or track on either Deutche Grammophone or the Decca labels, and that is a lot of titles. Since the search is the only means provided to browse the Qobuz catalog, it means that these titles cannot be accessed from Volumio.
If I add any of these albums to Favorites in the Qobuz desktop app, then these will after awhile appear in My Albums in the MyVolumio Qobuz plugin. When each of these albums is clicked, they do not contain any tracks, show a duration of 0:0 and pressing the play button does not have any effect.
Similarly, if I add individual tracks from any of these albums to Favorites in the Qobuz app, then some of these will eventually show up in My Tracks in the MyVolumio plugin. Curiously, these tracks will play. They will howver, show up in the Queue as "undefined", and Playback will not show any track or album information. Deleting a track from My Tracks will cause the error messge "Cannot remove qobuz:track". The track will disappear from My Tracks, and the track list will be updated with any tracks added to Favorites in the Qobuz app.
On a positive note, if I create a playlist from any of the aforementioned albums in the Qobuz desktop app, then the list will appear in My Playlists and be fully playable in Volumio.
The addition of HiRes streaming to Volumio is a major step-up, and the Qobuz plugin appears to be only a short step away from realizing HiRes streaming with usability on par with the rest of Volumio. Fixing the abovementioned issues is crucial, however, for making that happen.
I keep the Qobuz app on my Mac. I will search for an album in the Qobuz app then select it as a favorite. Once it is selected as a favorite in the Qobuz app it will appear under "My Albums" in Volumio.