I have been persuaded a few times. I say that tongue in cheek because each time I was the one suggesting it and actively looking for it to happen but I make usre my guys know I am making this incredible sacrifice for them! 'Cause I care, ya know?
Seriously though I am terribly picky when it comes to my sexual partners, I need to have some sort of connection with them and I have found lots of women I might be attracted to seem threatened by this. I do like a mixed threesome or moresome though...