Tvad,
YEs, I think the field coil concept is one that truly can open up some new horizons in sound reproduction, if done right.
Maybe this technology will get a foothold again somehow and prices will drop. I would not think it necessarily such a complex or expensive technology to develop these days if given some benefits of economy of scale.
I have my own vision of the ultimate speaker being something along the lines of an OHM Walsh omni with field coil driver technology applied to the Walsh driver for greater efficiency, etc.
With an omni design, you might not need a barn to prevent damage to your hearing since less sound reaches your ears directly.
Maybe someday....
I'd love to hear some good "Porcupine Tree" in a big room on a pair of speaks like the Classic Audios with the field coil technology. That would truly be awesome.