So I've been running iOS 10 on 2 devices; an iPhone 6s and a 6 plus. Beta 4 has made my 6 plus feel faster than iOS 9.3, and my 6s already felt that fast before this build. Based on how well it performs now, more than a month from release, it tells me iOS 10 could be the fastest release ever. I've always felt the 6 plus to be a sluggish fool. Like the A8 was built for the 6 and had to do what it could to handle the 6 plus' outlandish screen demands. iOS 10 changes that massively, and I can't wait to see what iPhone 7 brings to the table.