Depends on the persons. My bf and i have been dating for 9 years (7 out of 9 years is long distance.....still long distance now). He proposed to me last year. We are getting married next year. He said that when he met me at 19, he wanted to settle down ever since.
However, i have this guy friend who is already 36. he is quite good looking, very talented, making about 120000 US dollars a year, never lack of girlfriends. He still doesn't want to get married even he is already 36.So....i would say this really depends on the guys and their personality.