I love my Surface Pro 2! I'm going to provide some background here, but TLDR is at the bottom of the post. I've had my SP2 for over a year now, and while it's not exactly my primary computer, I find myself using it far more than I do my more powerful desktop. This is largely due to me being away from home for practically days at a time. When the Surface Pro 3 came out, I considered upgrading, but didn't because of the following issues, in order: 1. Cooling was terrible, and I'm a power used (Graphic design, such as Photoshop, Autocad, Solidworks and Catia, as well as occasional gaming) So constant CPU throttling was unacceptable for my situation. 2. No power cover. I have two for my SP2, as I regularly spend long stints (up to an entire 14 hour period) away from an easily accessible power outlet. My understanding is that the SP3 and SP4 can both be charged by high quality USB battery packs though, so that's an acceptable alternative to me so long as it works. 3. The SP3 is bigger. I've come to believe that the size increase is likely acceptable... but I still prefer the smaller screen, for increased portability. The increased cooling, and ability to use a portable USB charger, as well as next gen CPU and integrated GPU have convinced me that despite the amazingness of my SP2, it's time to upgrade. In all honesty, my SP2 is plenty powerful enough for me, but I'm often hitting the limits of my 4GB RAM limit, so if I'm gonna upgrade, 8GB is mandatory. This automatically excludes the i3 model, which would be almost perfectly on par with my current i5, but with much better battery life. Oh well. So this, of course leads me to the i5, which is likely powerful enough for all my needs, but since I definitely won't be upgrading to the SP5 when it's released, I need to consider the future as well. For $300 more, the i7, and more specifically, the Iris 540 integrated graphics seems to be a very smart purchase. With almost a 40% better performance rating, it would make most of my mobile 3D modelling projects silky smooth, and give me that much more gaming power when I'm ready to relax. But since I can't yet get the i7 model on Amazon, and the i5 is available for purchase right now, it has given me time to think. How much more power will the i7 use, compared to the i5? Computing power is very important to me, but since this is primarily a mobile platform, battery life is everything. If the i7 gets an hour or more less life off of a charge than the i5 would, then I'd probably rather have the i5. I know Intel says they are designed to consume the same amount of power, but we all know real world results can differ greatly from what the manufacturer says. Are there any tests comparing the battery life of the SP4 equipped with the i5 vs the i7? Does anybody have any real world experience with this? Thanks for any help you can provide! TLDR: I'm leaning towards getting an i7 SP4, but not sure if I want it if it consumes a noticably higher amount of power than the i5 variant. The i3 is not an option as it doesn't come with 8GB RAM.