the "best" corn head system dpends on what your next operation in that field will be. If you will be pulling a shank type machine through that corn shortly after combining then the more aggressive knife rolls will leave shorter pieces.

But the aggressive knife-type rolls also leave a thicker, non-anchored mat of residue which in 200+ bu corn can be a lot of material. That mat should generally be worked in as quickly as possible.

The fluted rolls tend to leave the stalk more intact and attached to the ground.

If you will be no till drilling into corn stalks, the more residue left attached to the ground (not blown to the fence line over the winter) and standing (not in a thick damp insulating mat on the ground) the better.

Most drills do not have significant row cleaning capability so the less aggressive rolls will be generally better.

There are exceptions to this of course but generally the choice of rolls should depend on the next operation in that field. jmho.

Jim at Dawn