"am 44 and he is 47, and my children are grown. So I really don't have to worry about disrupting the lives of my children too much. That is, a divorce wouldn't be a trauma to any of us. We would just split some stuff (money is not a problem) and carry on with our lives. Of course by then I may be too old to find a decent man, but I know that even in your 50's if you look good you can still find another older man who is divorced, widowed, etc. So I do not fear divorce or loneliness."
Since you've already thought it through to this point I wouldn't bother going through with marrying the guy. The end result is obvious.