El Capitan UI smoothness on Intel Iris?
My Mac Mini 2014 has an Intel Iris Pro graphics. Upgrading from Yosemite to El Capitan definitly improved the overall smoothness. Resizing Finder windows is buttery smooth, for example. Switching the preference panes is just as smooth as it was on Mavericks.
It's noticable in about all applications. El Capitan is definitly an improvement.