Yes I have the Plus version with the copper coloured top design.
If you have a particular VC1 demo in mind I can test it for you.
I did use dual boot early on with LibreElec, it worked but I wasn't happy with the performance so I went back to just android. I've not tested this again on Android 14. My main use case for the box is to use the Netflix, Prime, YouTube apps (which all work fine and support 4k and HDR formats etc. only downside is if you're in the UK then iPlayer isn't certified yet). I also have Kodi for ripped media such as dvd's, blurays, 4k encodes etc. - they all work fine.
As for audio, every audio format I've got has worked - I bought this box specifically for the Atmos TrueHD pass through capability, the DD+ Atmos works as well. DTS Master X works on the Android 14 builds.