Just for fun I thew this together based on Josh's measurements. Now, obviously room gain will throw these numbers around quite a bit, just realize this was only for fun:
The first is comparing the GH/OTH combo in comparison to my old quad sealed setup. The second is too see how far off it is from Notnyt's system.
Again, I know how many variables will change all this, but I was bored and thought it would be fun. The fun part for me is that compared to my old system, it's still a total of 4 drivers compared to 4 drivers, and 16kw of power compared to the same 16kw of power.