I bought the 64GB iPad 4 with Wifi a few days ago. I absolutely love it and using it constantly. I'm thinking of returning it for the 32GB iPad 4 with Cellular instead as I'm currently running it nicely with a good selection of content at 25GB. Quick question before I go to John Lewis right now... how does the battery life compare? Will I have to constantly disable cellular/wifi to get better battery (cellular, specifically)? Is it noticeably heavier? Is it FULL 4G now?