I think its nice looking but its not worth buying it when you can probably do most of this yourself, and not horribly complicated(compare to say, building a Hi-Capa slide set yourself)...
Obviously not, as Jerry said Japan is way way way way way overpriced
Its because they are underappreciated and deprived.

I'd certainly rather my own designs be etched/machined in and do my own work on building.
That's the fun of airsoft.