Microsoft's website says "up to 9 hours of battery life" the best I ever got was 7:30 hours on windows 8, and never more than 5 hours on windows 10. Has anyone actually gotten 9 hours or does that sound as impossible to you as it does to me? Also you might say: "but they say up to" and that's true they do say up to, but from an honesty standpoint I would hope that they'd at least try and pick a number reflective of reality. Also there's other tablets (HP Spectre, and dare I say the iPad Pro) which do get more or less the battery life HP and Apple market the devices as. The other frustrating thing here for me is, My Sp4 probably is even *worse* on battery than my SP3 and SP2 was. How is it that W10 is worse for battery than W8.1? Shouldn't each iteration have slightly better battery life if for no other reason than more efficient CPU and GPU chips? The 2016 Macbook gets about 1 extra hour of battery life over the 2015 Macbook as an example. And it's not even as if we have 4 physical cores in these devices, and we have integrated graphics cards, so what gives?