From my perspective, fucking a wife when her husband has no clue is a lot of fun. It's an added rush when you are "not authorized". Nowadays, being allowed to fuck a man's wife is nearly mainstream IF you are considering it from the perspective that a lot of people are doing it. But fucking the wife behind his back, will always be a "no-no", so there are lot's of risqué ideas to enhance the pleasure. I say, find a dude who has something to loose and you can trust, then have a blast.