I have heard crazy rumors of insane battery life with heavy wifi use. On average how many hours would you say you are getting between charges. I am starting medical school this year and will be in class 9 to 5 daily, and won't have access to a plug wherever I go. I'm trying to decide if the iPad is a suitable alternative to purchasing a Tablet PC. The main things I need are email, internet, and the ability to edit PDFs of 500+ pages which includes highlighting, underlining, text boxes, and drawing figures and arrows. Thanks.