We are currently looking at making a switch to ePMP from UBNT powerbeams and been able to just switch out a Horn would make the process a lot more financially viable.
A great way to help make transitions easier would be to engineer a Horn that could be swapped into a UBNT Dish.
Then we would only need to purchase horns for our other 5000+ UBNT clients.
If the focal points are the same, and the hole in the ubnt dish is bigger than the F200 base diameter, then maybe an adapter flange could be worked out(by a 3rd party).
But a different feed plastic mold just to cover this user case? very unlikely.
possible low performance aside, i think this kind of hack could make the FCC a tad unhappy if you live in an FCC area...