I went to The Boilerhouse when I was in Dublin earlier in the year.
There were quite a few guys there that night and it was easy to get what you wanted.
Some go there to hang out and chat, some go for romance (?) but I went for the sex.
I haven't been to mykonos in Cork as I'd like to avoid being recognized (it'd be just my luck a neighbour would be walking by as I went in.....)
If you want to experiment with a little gayness then it's definately worth a go.