Let's keep track of how iOS 12 is doing on different iPhones. I'd specifically like to know how people with an iPhone 6S are doing.
Device-specific experience thread
iPhone 8 Plus, Unlocked, 64GB. Running flawlessly here. No complaints so far
iPhone 6S
Finally installed last night, and it's been working quite well. The old features run smoothly, and the new features are mostly good (very minor issues like flipping camera in facetime not responding). AirPods linking seems to take place more quickly.