I have my watch for some time. Impressions:
Software 3.10
1) Amazing Black Screen
2) WiFi no issues
3) Music no issues, using it with Sennheiser XC-Sports. They have an independent volume rocker but everything is controlled by the watch with no issues. I uploaded mp3s from Ubuntu simply copying paste the tracks in Music folder.
4) Battery life amazing
5) GPS accuracy, good for my standards
6) Heart Rate a little high but acceptable for my standards
7) PulseOx, functioning fluently
8) Sleep monitoring accurate enough
8) Weather syncing works fluently and syncing with Garmin Connect as well.
I am not experiencing any issues for now and very happy with it.
Regards