Is there an efficiency factor banding sulfate of potash vs potassium chloride? For people who have it available or have used it what is the price difference?

I know of NO advantage to banding SOP vs potassium chloride. Unless one is fertilizing a chloride-sensitive crop such as tobacco or almonds. which have known sensitivity to chlorides. SOP does contain the additional nutrient sulfate (KS2O4) sulfur which may be of some benefi to crops. Potassium chloride does not contain any nutrients other than K and Cl.
Depending on local supplies, K2SO4 can cost 1,5 - 2 X per unit of K, more than potassium chloride.

The biggest difference between SOP and KCl is salt index and of course, you get S with SOP. 

If you’re banding away from the seed either is a good source of K.

Details for Crop Protection, Fertilizer, Soil, Nutrients, Field Crops, Row Crops, Seeding, Fert, Irrigation

Crop Protection, Fertilizer, Soil, Nutrients, Field Crops, Row Crops, Seeding, Fert, Irrigation