I've been in a FFM before. The 2 women were curious, but neither had tried anything with another woman before. It was a hot experience, but all they did was kiss a little. I think they were both waiting for the other to take the lead. Had they both been bisexual, I would have very much enjoyed seeing them together.

As for a MMF with a bi male, it would be a definite possibility. I'm bi-curious; however, I am not sure if I would really try anything. Some things are better left to fantasy. This could be one of them. Of course, if some good looking couple got me drunk, who knows....