It is a handy tool.
The coolest feature is the Spotify Connect which turns your MA speaker into a Spotify Connect satellite to play to directly from the app. (I know, Spotify is terrible, but it is an admittedly Connect is a very very good feature in both Spotify and MA). Sadly, it is very buggy when testing. For me it worked well for a while, but now it bungles Spotify encoding and plays very very slow and distorted
It plays my home library very well through my ESP32S3 DAC to my old 90s Yamaha AV receiver and amp. (Side effect of also being able to control the sound system via HomeAssistant and IR and use voice assistant on a MEMS mic.
Like others have said, the interface is very clunky and bad for browsing your library of local music, but oh well. I also wish it had a radio function for your local music.