For direct user interactions (such as opening a combo box) the threshold of perception is actually much closer to 30ms than 300ms. 300ms is usable but far from

For direct user interactions (such as opening a combo box) the threshold of perception is actually much closer to 30ms than 300ms. 300ms is usable but far from a pleasure to use. I found myself interacting with a Windows Server 2008 VM the other day (don't ask!) and was astonished how snappy the UI was, relative to today's machines (Windows or Mac).