General Scared a bit about iOS 8...

[Jessica Lares]

There are some apps that DON'T need background app refresh, but still have it. Turn that off for those particular apps. Same thing with location and other things.

No problems here on my 5S so far. I haven't updated my iPad Mini though and will probably keep it on iOS 7 just because there's too many apps that will either not get updated, or take until next year.

 

[Traverse]

The performance damage was done when iOS 7 introduced the new blur effects and animation. I would image that iOS 8 would run just as well as iOS 7 since they have the same visual demands, just with more features.

 

[T5BRICK]

I'd install it on the mini to try it out, but keep in mind that it'll run better on the 5c.

 

[madsci954]

Updated my 5s to the GM a few days ago. No negative performance in day to day use or battery, it's been the same or better than iOS 7.1.2. I updated my iPad Air last night and haven't really used it, so I can't judge yet. But initial use has been like the 5s, same or better.

I did clean installs for both, set them up as new, and manually added back my data