D. Gettis, Cadillac Williams or A. Armstrong for flex? Week 12?

After benching Jahvid Best and Fred Taylor, I need a third option. Which one is better? If you ask me they're all too similar. All my options could be either a boom or a bust, but most likely a fizzle on average. I'm leaning toward Gettis after his good game, but I think Cadillac could still snipe a touchdown with his job and performance in question. What do you think?