@shadyJ - In your tests, does it matter which direction each sub faces to encounter max. gain? For instance, if both subs are side by side but not pointed in the same direction does that impact the result?
Theoretically, it shouldn't matter, but in practice, it does matter. For example, if a port and a driver are mounted on different sides of the sub, the mic will pick more from whichever is facing it. The driver matters more than the port here, so you generally want the driver facing the mic than the port, because the port only produces deeper frequencies, and you don't get as much losses from deep stuff when the port isn't facing the mic.
However, in a room, it shouldn't matter as much since the energy is more contained in a small space rather than flowing out freely in all directions.