Maybe I don't understand (but I've never needed spiral-binding). Cool-factor aside, does this have much more utility than a regular three-ring binder and using a normal (and cheaper) hole punch to customize your organization?
I'm kind of loving my new mini-3-ring DIY binder/organizer at the moment... Super durable, flexible, wide range of accessories. I keep a pencil, pen, highlighter, reinforcements, divider flags, and post-its in a binder pocket. I still use card stock (index cards) for dividers... I can move around pages at will and purchase pre-templated pages or make my own. I can purchase a day timer (or knock off) agenda or print my own pages... Lays flat, hard writing surface.
How much better is an Arc? It seems like it would take longer to assemble an Arc, although perhaps it is more fun pushing the pages into place than opening binder rings...