Very interesting. The main issue I see is it assume all desktops to be equal. Responsive design is about supporting a range of viewport dimensions and not about about a range of devices.
If I'm on a desktop browser and my window size is the same width as a tablet, then rearrange things to fit in tablet size rather than keeping at the desktop size and forcing me to scroll left/right. The demos work nice when you change devices but when you adjust your desktop window you get the same site whether you're 800px wide or 1920px wide.
If I'm on a desktop browser and my window size is the same width as a tablet, then rearrange things to fit in tablet size rather than keeping at the desktop size and forcing me to scroll left/right. The demos work nice when you change devices but when you adjust your desktop window you get the same site whether you're 800px wide or 1920px wide.