I've had multiple people tell me the kill a watt US version will work 240 with no issues, so I'm interested in this conversation.  I found this link https://electronics.stackexchange.com/questions/90805/how-to-calibrate-a-kill-a-watt-meter-and-understand-its-hidden-service-menu
in that article it looks like the hidden service menu has an option to recalibrate the kill a watt to 220 instead of 110.  Maybe philip should try to change the setting mentioned and redo his test to see if it then shows the correct voltage? 
One of the people that told me just to use adapters and the kill a watt on 240 mentioned he has been using them in his mining farm for over a year with no issues on 240.  confusing...