Might be wise. I've never done a glory hole and don't think I'd ever wanna risk it. Even if it's not a man on the other side it might be some only lady. Or even a tranny!
I'd wanna know first but then I guess that would kind of make it a bit pointless.
Just head to an actual SWer for a session. Even a sensual massage. Debs! Going there again this week! I'll get to see and touch the girl!