When recording as the director, the button and option to record each guest is available by default. It's hidden behind Advanced controls. You have the option to record locally, to your own disk, or record remotely, directly to the remote guest's local storage.
When recording to the guest's local storage, quality should be near pristine, given as its not being sent via the Internet first. Recording locally, the video may have dynamic resolutions and varying quality, due to the low latency transmission. (&chunked-mode excepted)