I regret installing it on my iPhone 6. Almost everything is slower. As
kyjaotkb said, Messages is sluggish. If I haven't had it open in the last few minutes it can then take 4 to 6 seconds before the screen is anything other than white.
I think the OS is aggressively closing apps, not just sending them to sleep.
I'm waiting for 11.1, and am going to leave my iPad mini running iOS 10.
Not to mention bugs. Can anyone replicate this: Open Messages, swipe on the bottom app shelf until you get to the ... (more). Then try delete the Store app. Boom! Instant crash.