I have never found the concept of a glory hole appealing, in my life only a handful of ladies have been really good at BJ's, for the rest it was mostly watching them do it that was the turn on.
But even if I was super into it, i still wouldn't do a glory hole, first... it's a man, it always a man. Second your dick is super exposed. Who knows what kind of sick twisted thing the person is doing on the other side,
Watch this from this from the Shield:
Number 1 rule in this game is "Safety first"