Depends on the 40 something, depends on the 40 something, depends on the man.
I know some damn immature phsychotic 40 something women, and I know some well adjusted, mature 20 somethings. Same goes for men of either age range. It isn't universal. Age provides some generational conflict, but otherwise you're still looking at how well two personalities match up and the number of years is not the most relevant factor in that compatibility.
(ps - I didn't read the link, just my .02 on your question)