Angular Universal

I'm testing out Angular Universal for server side rendering (I love it, I think the guys on the angular universal team did an awesome job bringing server-side rendering to angular). I downloaded the starter kit from here. Then I ran the set up and viewed the results in the browser.

When the page loads it comes in very fast and then chunks disappear and reappear in a little blink. To show this in action here are some screenshots taken from the google chrome dev tools (Network tab with capture screenshots on).

Part 1: 382ms

Part 2: 400ms

Part 3: 925ms

Part 4: 1.04s

Question

Why do some components disappear at part 3 and then reappear at part 4? Also is there a way to stop this happening?

Edit 1

A module from Angular-Universal is preboot. With preboot there is an option for a buffer. I have set this to true, it works well for rendering the app. I see the static html in a flash but still have a problem waiting for the data to load. Here is a link to the Angular-Universal preboot module.

preboot: {
  buffer: true
} 

Do I require some kind of store to pass the data super fast between the server and client?