When Windows 10 was available i tried it out on my SP3 i5 128gb, but switched back to 8.1 after a few days. There was quite a battery drain, and some little things like no available brightness slider really bugged me. Now the question is, there are 4 days remaining for a free upgrade, should i do it now? What are your experiences regarding battery, overall performance? I really like the Metro IE in windows 8.1, because of the touch features and the low battery drain. How is Edge compared in Windows 10? Is OneNote fully working like on 8.1? (I remember there were some issues). Is the tablet mode an improvement of the 8.1 Metro UI? Sorry for the many questions, but i would like to hear your opinion and experiences W10 vs W8.1 thanks!