SlickSpeed CSS Selectors Test tests the CSS selectors in every browser, whether or not the browser included xpath. It is written in simple PHP and plain JavaScript. No framework is used in the suite JavaScript file, as the point of it is to test frameworks against each other. This avoids favoritism. Also, each framework runs in its own iframe, so no prototyping conflicts can happen. So that we can have a rough idea of the speed of running the CSS selectors.

Link: http://mootools.net/slickspeed/