This is tricky. I was once asked to do this by a foreign woman that I was dating. We had been going out for about 5 months anyway, and so she said that it would simply be like living together anyway. I thought about for a little while, and said that I hadn't made up my mind although I was still thinking about it. The result? She left the country abruptly, and I haven't seen or heard from her since. So I think I lucked out on that one. That said, I would consider doing it if the woman was attractive and there was a guarantee of sex in the equation.