I would doubt that you need the secondary speaker pair in a church, or, to be honest, any decent sized room. Sounds more like a feature for surround sound film score and recording use to me...
To be honest, I wouldn't anticipate any imminent cross pollination to other products. Roland generally allow exclusivity for a few years on any new groundbreaking technology, V-Drums, VK organ, V-Guitar - all of these took several years before they made any trickle down appearance. Stands to reason, really, as Roland need to recoup the R&D before going down-market...
The future does look promising, though.
_________________________
An arranger is just a tool. What matters is what you build with it..!