Most i’ve got in Windows on my Hi8 is 5 hours Youtube/browsing 25% brightness. Android around 4 doing the same with brightness slightly lower than window. Personally I would steer clear of the Hi8 pro it sounds like a nightmare looking through the forum, the Hi8 has been rock solid for me and the performance difference is not much according to Chris. Of course you miss out on Lollipop but 4.4.4 on the Hi8 is a good rom.