I’ve had one of these running for years, honestly I didn’t expect it to last this long as it looks really cheap

I use plexamp too with a large library so I can comment on the android side (I didn’t know some of these differences existed)

• the app has settings for audio quality dependent on connection type, including not converting hires audio
• as far as I can tell the EQ in plexamp is global across devices, though it has presets for specific devices -same on Android I don’t think you can manually listen to downloaded songs outside of the app

I’ll also comment that I sort all my music by folder and Plex does ok with this Not great, but it works