Choosing between implementing classes using the Class Designer (VCXs) or through standard code files (PRGs), it is simply a design decision. Using the Class Designer to implement classes offers many more benefits than creating classes in PRG files. With the Class Designer, you can create subclasses using the Class Designer or create instances on forms using the Form Designer. Along with being able to use visual tools for increased productivity, visual class libraries (VCXs) hierarchies can be viewed in various ways using the Class Browser.