Great implementation of Material Design, the best I've seen so far. With other material design implementations [1] I ran into problems with checkboxes, sliders and other design choices, as well as problems on mobile. I appreciate the design choices made for MDL. It also runs smooth on mobile and the form elements like checkboxes and sliders work really nice.

Also, useful documentation along with codepen and easy clipboard buttons.

Following.

[1] To name a few material design examples: http://superdevresources.com/material-design-web-ui-framewor...