My application time opening seems to have slowed down some but not too much. I think iOS 11 on the 5s is not too bad. Amazing for a phone 4 years old.
I did the upgrade to 11.1. I've been living with it for a full day now - a bit more than that actually. I finally was able to make my own poll!
The only reason I upgraded was due to the security patches as I was completely happen 10.x. I am happen more.
Animations are horrible. When unlocking the phone, the animation is almost non-existent now. It does;t stutter so much as it just pauses, and kind of skips the animation.
Scrolling is slow in most places that I can scroll.
When I select the area to type a text/iMessage, i get a delay before the cursor appears. Typing isn't too bad, in messages, as it lags a bit behind my typing, but for the most part it keeps up. It feels sluggish though, and sometimes does lag behind my typing.
Overall, the entire user experience has been degraded to the point where I don't like the phone anymore (can't help but continue to state that this is on purpose)... If only Apple would have issued just the security updates, I would have skipped iOS 11.x altogether.
Currently, I am not a happy person (withy phone anyway). More to come as i continue to use it. I will add that it does't seem as bad as when I upgraded my 4 (or was it 4s to the latest iOS) many years ago. I pulled over one day, to use the phone, and literally almost threw the phone out of my window onto the concrete. Fortunately, rationality took over, and I didn't smash it.
IMO, I advise not upgrading unless you want the security updates. Unfortunately, I always recommend installing the security updates, so this is kind of a Catch 22 situation for most people...
EDIT: Forgot to add that my batter life went from 100% to 57% in six hours with only moderate use. In all fairness, this is the original battery, but it lasted longer under iOS 10.x.