From the top of my head, (this is all very opinionated) "Farewell, My Childhood Self", some of the Homo Perfectus stories, and "A Jung Hero's Adventure" were all pretty good, but they weren't the greatest either. While they were a little more than a lunch-break's length, their scores weren't the tip-top.
Also, to clarify on # of pages, I'm talking more about overall rather than the longest linear path.
And Bo says it better anyway : It's all about the content. I wouldn't be too worried about the length of your storygame if I were you.