I should also add that of my top 10 earners, 7 almost never or never sold at other sites, and vice versa. Which leads to think the best match is hugely manipulated, much more than on DT and SS since the overlap between good sellers is much larger there. This far-off best match plus the fact that recent files (of 2010) sink to the bottom and never sell at all made me stop uploading even before the royalty cut announcement.

I should also add that of my top 10 earners, 7 almost never or never sold at other sites, and vice versa.

same here, weird business this is......

One thing I have learned is that different sites sometimes cater to different types of buyers.  Of the 40ish images common between DT and SS, different images seem to sell on the two sites with maybe 1 common image selling on both sites.

This is especially true on footage...  I have my top 100 selling video clips from Pond5 on every agency I sell video through, except iStock, and most of it doesn't do nearly as well. My top selling clip on SS sells considerably less on Pond5.  My best selling clip on Revo has only sold a couple of times on Pond5.

So, when I'm out taking pictures or shooting video I don't think about what any one site sells more of because what's popular on one site may not be on another...