iPhone 5S, original iPad mini, ipad 3 and iPad air all showing improved battery life, much more responsive. All updated OTA, No issues with download or installation, on launch day.
I imagine a majority of users have experienced the same - not hearing issues from any of my friends with Apple devices, and seeing nothing in the tech media, except an unfortunate few who have taken to the usual forums to air their issues.
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Things aren't bad, a few users are affected. Other manufacturers have exactly the same complaints. No amount of beta testing can cover every single situation and combination of factors. When 20million+ people update it's inevitable that some will experience issues. The issues will be tracked down and fixed and in the meantime those affected can quickly restore their devices and wait for the fix. No issue here, it's really not that important. First. World. Problems.