Yes, CO couple multiple times. Mostly while we were travelling elsewhere during CO visit week (how on earth our prearranged trips always collided with CO visit that was arranged on busiest vacation period?). We had good experience with them, home was always tidy after they left, maybe even tidier than originally. There was always some kind of token of appreciation, flowers or card.
Once we happened to be present while they were staying with us. Ofcourse they did their routines and that way were very much away. But during dinner and evening we had interesting discussions, I was not the exemplary brother at all, but I did not felt like there was pushing or intimidation. It was just interesting discussion with challenging viewpoints coming from both sides. Wives spent their time again mostly together sipping wine and watching TV. Both the CO and his wife took time each day around 20-25 minutes to read magazines and discussing them together in their room and day before public speech CO rehearsed it for a while, even he had held it already multiple time. Very thorough in that sense. Food we offered was always well received and appreciated, breakfasts we asked them to arrange themselves from existing ingredients as we were working and kids went to school (this visit wasn't during the vacation period). I must say that this visit in our house for me was far more refreshing than the program of CO visit itself. I really have fond memories of that visit.
CP