Oscar, welcome. This question has been raised here a couple times in the past and Axiom audio expert Alan Lofft has stated that the requirements for surround speakers and front speakers differ. The diffuse sound field that's appropriate for surrounds isn't considered to be the best solution for the front speakers which benefit from a more precise imaging.
Note that the QSs have no rearward firing drivers and don't attempt to duplicate what Bose and a few others have attempted to achieve with multiple drivers configured so as to direct their sound to the rear.
