Been there, done that and would absolutely do it again.
It started as an "accident" during a 3sum with a GF, little more male contact than we intende but it got me curious. A different GF told me she thought it would be hot to find a guy to suck my cock with her.
Once that happened (and she knew it would have this effect) I was curious about sucking a cock.
My wife and I have shared our bedroom our entire 13yr marriage but a few years ago we finally pulled the trigger on finding a guy to share our bed and US for a night. There's nothing hotter than kissing the woman you love with another man's cock between your lips.
(Except ,aybe sucking that mans cock while your wife is rimming his asshole and he cums..... who caused it? shit was hot!)