WP gets 7% most often, unless negotiations cuts that down.
I am not sure about elsewhere, but 7% is a premium here in western IL.
I just sold me farm last week through LandGuys. They got $5500 for selling my farm. A seller himself can get a great amount of exposure on their place with places like Landwatch, Craigslist, social, etc etc.
My experience with WP is that they are "too busy". Classic economics - lots of places to sell and nobody gets "special" attention. I bought my farm from WP, and got it at a DEAL because it was not marketed correctly (my opinion).