I think that season 5 actually holds up better on repetition. Even though it has some glaring Whedon tropes (Yay Wes and Fred are happy together - oops) it feels less draggy in repetition.

The repeated viewing is also why I like Alien3 the best of the series. The first two are so imprinted in the brain that I know exactly what is happening at every moment. The third one was a weird surprise when I saw it again - definitely a Fincher movie (even at that time he was the unknown music video director who was screwed up the Gibson plot and killed Newt)