Dulles is decent, but is slower and less convenient than smaller airports. There are trams that take you between the terminals and the check-in/baggage claim area. The trams add extra time to your travel. The airport is comfortable with plenty of foods and shops, though expensive(as all airports are). It is easier to navigate than many large airports. Sometimes there is a long wait at customs coming in from international flights. Parking reasonable and easy to manage. The Pay-to-go machines are very convenient. Security lines are fast, as long as you follow directions. The area before you go through security is not so comfortable. There are no restaurants or places to spend time with your family before going through security.