It doesn't hurt for a 20 year old lad to have a few oldies about for riding. They usually come with a house which is handy for those weekend riding sessions. I wouldn't take one seriously though if i was you. Not many women look after themselves after thirty and ending up with a middle aged women who has lost it when you are only 23 is a Big NO NO.
I personally preffered older women but only up to a point. Once the young women are over themselves and acting like proper women then i ride them. You cannot beat the body of an early 20's women.
I would say ride older but for relationships around your own age is best. You should also remember there is plenty of time left. At my age i really appreciate women in there 30's and prefer them over any other age. I am just to old for 20's they are to manic and busy.
I think the main problem with older women is the baggage they come with as older people have issues. Someone previously has basically screwed it up for you and the rest of us and they are beyond repair.
I have lost count of the women i have dumped because they are blatant nut cases. Great bodys plenty of action but some ugly issue will raise it's head brought on by something someone done to them years before PPPfffff Madness, I leg it.