I know a few people who have been (both women), and independently they both said that on the nights allowing single guys it's pretty sausage-y. The women have their pick of the available men, who crowd around those women who seem approachable/available.
Based on this (very limited and totally unscientific) sample, I'd imagine in most cases it's going to be like the typical situations involving sex, attraction, men and women - excess demand and limited-supply from the male point of view. Probably a lot of fun for the women, though, especially when you account for the fact that they might also be interested in the other women there.