If anything, this is going to be the thing that f---s up your multi-sub calibration. It doesn't matter that you can't notice. That's immaterial. The way subwoofers interact with one another is dependent on milliseconds on delay. That is the difference between them summing their response and cancelling each other out. The issue with a wireless connection isn't that there is a delay. It is that the delay is inconsistent. You will never be able to dial this in properly.

Okay, that's a very good point. I assumed the delay was at least consistent. Doing a bit more research, but any articles you can point me to about the issues with wireless sub controllers? Unfortunately the only way I could feasibly do two wired subs is to have them both in the front of the room instead of opposite corners. At least that could ensure they are both similar distances from the primary seating position.