[BoomieMCT]

Here are some more plots that verify why I wanted two subs instead of one.

Blue: Both Subs
Pink: Right Sub
Yellow: Left Sub

I did measurements from all the seating positions (second chart) in my theater room and they were all smoother with two subs. Note the yellow line - that is from laying on the floor. I also tried putting them out of phase and basically eveything below 50 Hz went into the ground.