Specialized Drop-down Editors
With DropDown, you have complete control over creating specialized drop-down editors. Attach your logic to the spin buttons and your own drop-down form/editor to the drop-down button. For example, you could place a DataGrid in the drop-down portion and code its row selection event to display a value from that row in the header portion.
Adaptive Drop-down Layout
You can explicitly set the width and height of the drop-down or have it sized automatically to fit the content.
Expandable Above/Below the Header
Configure the WPF drop-down box to display above or below the header portion, or set the direction preference the control will use if there is enough space available on the form.