I currently run a 6620 and 4420 that throw the hammer and gusset out the back or up into the combine because they break or wear off. I have just purchased a 9400 that has the curved gusset vrs the flat gusset like the 6620 or 4420. I was wondering if it is worth the $1500 it is to update to the tri-rotor or is this not a problem with the curved gusset. basically i am wondering do these throw hammers out too. thanks for any help