There's an article up on DC Watch about the opening day now. It's in Japanese but worth looking at just for the many pictures of the Club House and the exhibits in it.
Look out for unreleased items like the Pentax Memorica and Metalica, as well as a Kore Jana Robot version of the Q.
They are also gauging interest for Club House special edition Olive green version of the K-70, which I must say looks really nice even though I've never found the K-70 particularly appealing.
The article itself has some interesting comments from the journalist. It explains the idea of the Club House as a locations for the developers, customers and retailers to exchange views. Interestingly, it seems that they have aspirations to open similar venues overseas. I wouldn't hold your breath on that, but it shows they are not determined to focus on Japan only.
Article in Japanese:
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