I've run 8010's for years and now an 8120. I grow mainly corn. I really have no complaints about the sieves in the combine.
Run the right concave modules...... in the right place.
Run with the bottom sieve OPEN, and clean with the top sieve.
Run the pre-sieve in notch 3 or 4 (I think that's where it's at).
The one drawback I see to the way the system works is with the yield monitor, when going up and down hills it is not the most accurate.