I did investigate these comic book boards before I started making mine. The problem with the comic book boards is that they are far too flimsy. They fold in half very easily. Some are acid free though and that's good. Think of them as FQ cardboard inserts. They are about that thin (very little support). But, again I suppose it's a personal choice. I think anyone who wants to try them should. Just bookmark us in case you decide to upgrade to something much more sturdy.
MTS you're absolutely correct. They really should be used upright. On another note, those smaller boards are nice to have because those seem to be the ones you "go through" the most looking to match your main fabric. Also, you can approximate how much you have just by looking at it sitting on the shelf. There aren't too many storage methods that allow you to do that. (And they fit nicely into drawers.)
Quiltmaker, I really do love my boards and the way my fabric looks. It is more inspiring to me to have the visual I now have. I've used plastic bins, tubs, bags, ruler folding, and stacking. My preference is the boards. I do agree with you completely about newbies - they should buy fabric, thread, templates before storage items unless their using cardboard (and some are).