If they are Dual 2s i would go with the mono. series to parallel would bring you at 2ohm and the mono amp would be more efficient 2ohms then the 2 channel. Most 2 channels are made to run 4ohm bridge and the farther you drop them in ohm the more heat,distortion ect... you get. And no matter what the subs are wired to as long as they are wired to where both have the same final impediance per sub they will always "split" the power