Considering the size of your room, I have no doubt that a subwoofer would not be easy to integrate or beneficial - in my experience subs should be far from the main speakers - I had mine 5 feet back from them. I also found that when using the Lamm ML3 with the XLF it was not possible to integrate the WatchDog subs properly in this system - I have now an idea why, it is not relevant here.
As far as we can see now in this thread we can get the idea that Zellaton's do not integrate with subs or with people liking them

. I think it is a false idea, worth discussing.