I installed this yesterday and it's not the easiest of plug-ins to do so. However for doing it made the site a lot more responsive. The main problem with this plug-in isn't the plug-in but the web servers.
With this out of the way this is some notes from the field on how I got it to play nicely:
1) Add each function one at a time and test thoroughly on all pages.
2) Minify is by far the biggest gotcha, I couldn't get it to play ball with my CSS so I manually minified the CSS before uploading a fresh copy to the server.
In browsers whilst testing use privacy mode where possible, this means you see what the users see. You could disable the option to by pass admins but it's easier to use the browsers private modes.
Overall it took me a couple of hours to install and configure the settings and do fault diags for weird cache issues.
Export your settings once you've finished and keep in a safe place...