The pricing of the RAAL ribbons is high, but still realistic for the performance level which is very high.
I imagine this one is aimed at the very well heeled, given the talk of limited editions of 12 for the cast bronze woofer enclosure.
There is a down-market version also mentioned in the 6moons article.
There is nothing intrinsically expensive in the concept, though, so I imagine one could experiment with the configuration with pretty cheap drivers and see some interesting results. Really, I think the configuration is the clever part in this.