To put it mildly, real connection and passion. I've never kissed a man. My wife and I shared a man orally and I have received oral from several men. I also went to a male masseur for a year and he loved sucking me and touching me and I enjoyed that immensely. I have never rubbed my body against a man, savoring the sensations. In college I was picked up by one of my professors who took me home to his wife and I fucked them both. So I have never had a man inside of me which I think would be extraordinary. But I wouldn't want that without him being a nice guy and there being a connection between us. I always wanted my wife to have passion and connection with her lovers more than just .... well, you know.
I have a current desire to experience a man completely and passionately. Having a woman watch and support would be amazing. Especially if she encouraged me to go all the way.
I wonder how freeing it would be to a man to have the woman he loves support him and his desire to not only enjoy her sexually but to also have a man in his arms and mouth (at least) and feel it is ok. In our case it deepened our feeling for each other.