Distributed Bass Array configuration

Please, I don't want to debate the merits of the DBA nor of those who espouse it. I am considering adding two more subwoofers to a system that has two already. To those who use a DBA,I am interested in how you have configured them, specifically--
  1. Do you run in mono, or do you split the array to run in stereo?
  2. What is your approach to setting phase (delay) among speakers that may be facing different directions and are different distances from the listener?

@clio09 I have the Morel Ticw 1058ft Titanium series 10'' subwoofer 8 ohm. You have experience with them?

@brunomarcs no I do not but have been intrigued by Morel and want to try out a set. I built my own DBA as well using Dayton Audio drivers in sealed enclosures. I do not use the Dayton Audio amps, but rather a pair of Bel Canto mono blocks to power the low end. I have an Accuphase F-25 for the active crossover with low and high pass filters.