Most bros seem to assume the older WGs have been going for years? I have known a few that started late in life, like around the 25+ mark so they had some good experience but were no way jaded or worn out (yet). Money problems can hit at any age.
It also appears we judge WGs as being on the "older" side once they get into their late twenties (or even earlier)? On that basis I voted for switching between younger and older but it's a tough call. Line up a beautiful fresh 18 year old next to the beautiful older, say 28 year old and I just know I am going to pick the 18 year old.