I say a mask is better. The facial expressions that a woman gives during sex, play a great part in sexual arousal. As far as security is concerned, that is kind of pointless to think about. When a person does beast porn, there are all kinds of factors that can give them away: birthmarks, tattoos, and body shape. Plus, the contents of the room can be analyzed. In an age where everyone has probably watched at least one beast porn video, I am sure that a person has recognized their neighbor in the video by the contents in the living room seen in the video. If the FBI wants to know who is in the video then they can find out who is in the video. They would much rather spend their resources on uncovering human trafficking, drug busts across the border, and on serial killers. $250,000 is a lot of money to spend on tracking a woman out in the middle of Kansas who decided to let herself get fucked by Scooby-Doo.