That IS a surprisingly low number. My stab in the dark is that there were quite a few models available at the same time, and speakers such as the HDT were getting a LOT more attention. Things kept rolling along with more and more new models, and perhaps the NFX was squeezed out of popularity (at least the little that it did have). I wonder if the small full range horn had some of the same experience? I know that it started out to be popular, but there isn't as much now about it. I even downloaded plans, but they didn't float for long as other projects came into being.