The shoe on the 9690 is the same, but they changed the motion of it so that it is more efficient, and put the turbine style fan in it which provides more even air flow through the shoe. The result is more cleaning capacity to go along with the increased capacity of the rotor. About Fieldstar: It is a very user friendly system, and should come with a GPS receiver. Also, a new yeild sensor has been introduced for 2004, and I believe there will be some sort of campaign to update the 2003 models at little or no cost. The new sensor reduces slope sensitivity by 88% and is temperature compensated. It also has a higher resolution, so it is more accurate in lighter crop conditions. The results from testing at the University of Kentucky have been very positive.