I am an AMS failure. I ran a display ad, not long after AMS started up, I think. It did okay. I don't think I lost money, or if so, not much. I currently have two AMS sponsored ads running. I haven't lost money on them, but that's only because they aren't being displayed much nor clicked on in any meaningful way. The bids are low, the daily spend is practically nothing.
Plus, I came upon a book the other day that had 166 pages of sponsored ads featured beneath it. I ask you, who scrolls past the first 5 to 10 pages? I mean if you are displayed on page 144, who cares?
So tell me, are AMS ads still worth it? And if so, how deep does one's pockets need to be?