Well, there are only so many 'days' Kiefer Sutherland can live through! :lol: It's better to end it while it's going well, rather than hanging on until they are forced to end the show.
Which is precisely what I think Alias should do. JJ should tell the story he originally set out to tell, rather than dragging storylines on forever, or scraping the bottom of the barrel to come up with new ideas.