It actually went really well. I switched some stuff up partially as a result of things we'd been talking abut here, but also because I felt like the best way for me to go into the situation was without the expectation of sex, but also in complete control.
I had him come visit me after work, we hung out, went to dinner and just let things happen. It was super hot, and afterwards, I felt - and still feel - totally fine with it. It totally melted husband's brain, and sex has been absolutely crazy.
Between fucking, we've talked a lot about it to make sure we're both totally cool and we really are. He is still crazy turned on and would like me to do it again if I want. After all the talk here, I kind of went into it thinking I should have really strong feelings, worries, etc but in all honesty, I don't. It was sex, it was a lot of fun, but that is it. I was able to give the guy a hug afterwards, see him off on his train and be totally comfortable with myself and my marriage.