"PR" often stands for "Personal Recording" or "Private Release," indicating it might be a recording from a live stream or a TV broadcast.
Verify if it has original Japanese/Korean/etc. audio or a dubbed version. To help me write a more accurate review, could you tell me: What show is actually playing in the video? Where did you find or download it? prbackup ep 108.mkv
Look for "blockiness" in dark scenes; a low bitrate will make the image look muddy. "PR" often stands for "Personal Recording" or "Private