I have to agree with Artian - it's true that you can get drama and unreliability in women of all ages. But one thing I can maybe understand about the core of what mnaz21 is saying is that it can (maybe) be harder for younger women to express themselves/vocalize their thoughts or insecurities.
Let's also not forget that one thing that may not have changed much over the years (not sure, just an assumption) is that females are raised to feel a level of uncomfortability and, in some respects, immense guilt surrounding sexual relationships (at least in America). And a result of that is often an inability to relax about the feelings when meeting a new potential mate/sex partner/etc.
I think the conventional thinking that women reach their sexual peak in their 30s is to do more with the comfortability with concepts of sexual matters, which comes with life experience really, moreso than the experience of sex itself. The end result would then easily be a more no nonesnse take on dating. Some women reach that comfortability in their 20s, others their 30s, and (judging from a few of my girlfriends) not until their 40s. It's a mixed bag really, but that's life
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