One more thing to consider when seperating out roots is that the overall quality of your entire lot goes down. I'm not referring to three or four extra special roots (shape, age, size, etc) I'm talking about selecting out the top 5 or 10% and trying to get a better price for those. Most generally when guys do this, they lose money.
I can typically move those special lots as I have one buyer who looks for just that. However, they are hard to come by as most guys understand its normally not a profitable move.