Personally, in MMA, I have no problems with somebody arriving with a Slice type of beard; chin harder to hit? probably. A bit of padding to smother the power a bit? possibly a bit. Abrasive a pain in the ass if in your eyes? Sure.
Come with it if you want, I am all o.k with it , but also knows one thing: I will get every single advantage that I can out of it, including pulling it, holding myself on it if needed,pulling it and striking it into your own eyes.