In 2014 I purchased 16 rows of Zippers for one John Deere 1770 planter. I planted cotton in one side (shown in left side of photos below) of the field with regular V closing wheels and the other side (shown in right side of photos below) with Zipper Closing Wheels.
We got a hard rain a day or two after planting. Normally with a hard rain, the cotton plants will have a hard time coming up or getting through the firmed soils. Cotton is very susceptible to crusting.
The Zipper Closing Wheels left the soil over the seed row mellower and more cushioned than the soil over the rows planted with regular closing wheels. After the hard rain, the mellower soil didn’t crust as bad as the flatter soil surface left by the regular wheels.
Five days later, cotton began to emerge from the rows planted with Zippers (see photo below). It was not yet coming up in the other rows.
We later took an aerial photo of the field (see below). The stand was much better where the Zipper wheels ran. There were more skips in the left side where the rubber wheels ran. My son attributes this difference to quicker emergence and less crusting with the Zipper Closing Wheels.
This year, I equipped four more planters with Zippers.