We really like the component based UI of Composer. However we came across a few problems that prevent us from using it as a replacement solution to Zurb/Foundation. An example is the "Button" component. Drag to UI. Excellent. I have a button. Now I want to customize that button (beyond the attributes in the UI). There isn't a way to toggle to the HTML. At this point you have to export to HTML, adjust and re-import. Sort of defeats the purpose.