In general, the best quality is only available through an ADP option.
There should be one or two simple-streamed variants (companion app is optional) and one to many ADP options (audio and video streams are transparently downloaded and aggregated locally, this requires the use of the companion app). When browsing a Facebook timeline or opening a Facebook video post, Video DownloadHelper offers several variants for each detected video. Video DownloadHelper 7.3.4 now includes support for downloading Facebook videos !