I don't have time in my day to sit down when I eat (I've recently realized I'm always standing when I eat), except for lunch, let alone watch TV. That's where Netflix comes into my life. I know I'm a little late on Six Feet Under, but wow, better late than never. The dark, sarcastic humor, the filmic scenes, and the diversity and quirkiness of the characters combined with a pretty solid story line kept Six Feet Under at the top of my queue until I had ran through the whole series.
This series finale is the best I've ever seen.
Obviously don't watch it if you intend to watch the series. I can't imagine that the emotional impact would be as powerful on a viewer that doesn't know the storyline, but for what it's worth, do a little research on the characters and watch this finale. Even without the background story on the characters you'll be able to appreciate the concept of this finale (which goes ever so perfectly with the series, which is, in short, based around death), the aging of the characters in these final minutes, the drama, and how perfectly the film is paced to Sia's Breathe Me.