http://freelawproject.org/2015/03/20/what-is-the-pacer-probl...
http://qz.com/283772/why-pacer-should-and-should-not-be-like...
https://freedom-to-tinker.com/blog/sjs/making-excuses-for-fe...
There are many more if you take time to peruse the Re: PACER document and click through the citations.
https://www.youtube.com/watch?v=HA4Z9LEJSBw