Very nice and easy to use! But very often the test fails. I've got no idea why. When I test the site under the original google pagespeed link the test works. Also I have an improvement suggestion: Why do I have to make TWO tests for mobile and desktop? If I go to the google test, I have both in one test.

Consistently reporting wrong information (for ex. "Enable Text Compression") and throwing a warning that it's using an old version of the API for a few months now.