The product demonstrates the ability to display quantity inputs for option values and compatibility with another extension -  Live Price  (calculates the total price appropriately to the entered quantities). 

The  Live Price  module provides the price updating on every change of option quantities (taking into account that some option values have additional price modifiers, like +10 or +15).

The  Live Price  module (as well as its improved versions  Live Price PRO) is not included in the package of the Quantity per Option module. It should be purchased and installed additionally (if the dynamic price updating is needed).