If you don't have the right room. That translates to one with volume. As all know, horns are very directional. So, unless you can sit in the exact 'sweet spot', you lose the total effect. My first experience with horns was with a single K-Horn, yes mono days. Blew me away. Of course it was a Marantz/McIntosh/Vinyl chain. Took me twenty years but I build a room for a pair and till this day I have not found anything better.
Why not horns?
I've owned a lot of speakers over the years but I have never experienced anything like the midrange reproduction from my horns. With a frequency response of 300 Hz. up to 14 Khz. from a single distortionless driver, it seems like a no-brainer that everyone would want this performance. Why don't you use horns?