battery life concern, is xbmc a good option?

Hi everyone,

I'm going to begin to start having to fly fairly often for work and i'm definitely going to want to use xbmc on the plane. My concern is over battery life. Does anyone have any experience with different media players and their affect on it? In the past i know that XBMC used to hammer a cpu on just about every OS while just sitting at the skin, horrible for battery life. Thanks for any help!