That has made me very cautious to use this for any serious amount of mounting.
Edit: Apparently there is a section on that page about it, but does not give a ton of confidence that it won’t give me a lot of issues.
I also had a Billy sat next to it, and did similar to this (but again not racked), with all of my AV gear inside. The door was great, it'd make any status lights diffuse and so they wouldn't interrupt watching a film in the dark (and my old Sky box used to have annoying blue LEDs with an animation when playing back a recorded show), but at the same time remote controls still worked through the glass. Literally best of both worlds. I cut a big hole in the back for cables, which also served well for airflow. I considered adding a fan, but never needed it. I suspect there would be issues with negative pressure doing that though.