Person of Interest - long or short dramatic presentation?

I'd really like to see Person of Interest get at least to the voting page for the Hugos. Tactically I think it doesn't have a snowball's chance in hell of winning in the long form, or even getting to the voting page: Gravity is almost certainly going to win, and Orphan Black S1 can make a much better case for being a single coherent narrative as a TV series. Then there's Thor 2, Man of Steel, Hobbit 2, etc. etc.

So I'm looking more at individual episodes for the short form award. I'm inclined to think that 2-21 "Zero Day" or 2-22 "God Mode" are the most SF-nal - 2-21 is the one that reveals how The Machine is evolving its consciousness, 2-22 shows what happens when an omniscient AI is in your life, but I think on the whole 2-21 is the one I prefer. Or I may just nominate both.

Any thoughts? Or is there a better contender I'm missing?