Does a circumcised man last longer than a man who isn't?

I don't believe it has anything to do with it. The ability to "postpone" ejaculation is a thing that some men learn how to do and some men don't or can't. Generally the younger your lover the sooner he will climax, but also will be able to become erect again sooner. With years of experience the truly great lovers (those who are unselfish and focus on pleasing the woman) can make love for hours and produce multiple orgasms for their partner.