I had a small portfolio with Pond5 for several years and sold photos for $12 (full size) and PSDs (only a few; they're more template-like) for $25. In June I uploaded most of the rest of my portfolio there and changed all the photo prices to $10 (full size).
I have opted out of the various partner deals -which is possibly why, after 2 sales in July, it's been nothing since. Given that Pond5 will reduce prices if they want to, I don't see any reason to lower mine further.
As far as the $449 - $795, there are distribution agencies such as Westend61, Mint Images, Blend Images and a host of others who license via Getty and the high price collections at 123rf, Shutterstock, Adobe, etc. Their prices are the same everywhere. I don't honestly see how it works to mix all these prices together, and Pond5's price slider in searches has such a tiny space for lower prices, it's hard to say you only want to look at images $25 and below.