I think it's a great idea for kids, but I can see two doubts for potential buyers, durability of cardboard and cost to replace it if needed. Public awareness should increase, I suddenly came to know about Labo existence when advertising started, and I already saw the ad at least twice, although I don't remember whether also on TV or on the net only.
Edit: OK, so Ninty will provide carboard design patterns for free, this should settle the cardboard issues for users with enough manual skills.