If the only time they would use the Generate PO function from Sales Order is for drop ships, you can setup a warehouse called DS, and use it instead of the traditional Drop Ship. In the Generate PO options (in PO Options), you can choose to have the customer's shipto address copy over to the shipto on the PO for ALL types of POs, not just drop ships. This gives you visibility of the item coming in and going out AND is great at prompting you for an order that should be invoiced and has not been because there will be QOH of the item in the DS warehouse.