Please share your experience. I have the exact same question. I need to take the JL flight to NRT. But I need to arrive at the airport in early afternoon to escort my family to take another flight. I would love to drop my luggage and go through the security with them and wait in the lounge. Or drop my luggage at the airport and hang around for five or six hours. If that is the case, is there any place nearby or before the security that is worth spending few hours?