I'm confused. Do you have to fly out of RFD? It says no where on the TCs that I have to. From what I get, I could do MCO-DEN-COS-DEN-MCO. However, I don't wanna buy a ticket and get stuck with the bill. Or might I have to do RFD-DEN-(any airport ua flies)-DEN-RFD? What about international, like SYD?