I have used Kansai airport for many times in my travels to/from Okinawa since (until the recent opening of the new Nagoya airport) the alternative was to fly to Narita and then take the 90-minute bus ride to Haneda. If you can communicate in Japanese you will have no problem with airport staff. In the past this wasn't always the case. A westerner that spoke fluent Japanese would be greeted with dumbfounded looks so it's safe to say that airport staff have become more cosmopolitan over the years. The only complaint I would have is about the scant collection shops eateries and services past the security checkpoints. In all other respects this airport is wonderful. It's so well-designed that it never seems crowded even when it is and the free wi-fi is a definite plus allowing you to be productive while you are killing time during layovers.