I have an iPhone 6 and I feel like iOS 10 may be the pinnacle OS for it's design. Other than a few simple tweaks (like the new control center), I don't see much difference or appeal in 11 for those of us owning older devices. The risk of system lag is too high to download and try for me. Right now, 10.3.3 runs buttery smooth on my iPhone 6 and I've made the mistake before of upgrading software beyond a phone's hardware capabilities. So who's running 11 on an iPhone 6 (or older)? Your thoughts? Is there any real change that benefits your experience?