The flow visualization is really great, especially how it will let you see entry and exit pages. However when you place the page dimension on Entry, you see the top entry pages by traffic volume. If I want to see a specific page that isn't in the top five, I've added an Entry Page as a segment filter to see it (red arrow below):
I keep thinking there should be an easier way to specify a page. Is there a way to do that without having to use a segment?