Hm, I'm not sure I'd call Midnight Cowboy or Platoon (both Oscar winners) downers. I was fascinated by the journey of Joe Buck and Ratso, but the way I'd be fascinated by two Martians traveling through their alien landscape. It didn't leave me feeling down. Platoon was so overblown I couldn't take it seriously...Oliver Stone showing off. I'd say Full Metal Jacket came closer to being a downer than Platoon.