Myers laid an egg for my team too, but I feel he's coming back this week. The matchup is near perfect and there isn't a Thursday Night Football curse over this game. Gates, like you said, has been overshadowed by Alexander, but will be stuck in a pass oriented game b/c of the recent explosiveness of Cam Newton.
Myers, with the exception of last week, has been targeted much more than Gates, and would be the better option in ppr formats. Yes, both are pretty close, but I say go with the big BM.