1. Itinerary: Incheon Airport is much bigger than Gimpo Airport, which means Incheon Airport has more duty-free shops and activities to choose from. If you want to shop at the airport, Incheon Airport may offer more choices.

2. Mode of transportation: Gimpo Airport has a subway directly leading to the urban area, which may be more convenient for passengers who need to travel frequently between the airport and the urban area.

3. Accommodation: The accommodation conditions and facilities of the two airports are also different. Specifically, Incheon Airport has more duty-free shops, and Gimpo Airport may have more subway choices, which may affect the choice and demand of accommodation.

Generally speaking, the two airports have their own advantages and disadvantages in terms of itinerary, mode of transportation and accommodation. When choosing an airport, you need to consider your specific needs and preferences.