Hi, coming back to this one. I have now bought some 4000's to be used as fronts and moved the 2500's to rear. It works ok and I think it is better than nothing if you can place then in a reasonable way. I have daisy-chained mine with an Y-splitter so I only needed to have one Powerlink cable from the Avant around the room. In order to let the black boxes on the 2500's point inwards (I felt it better that way than outwards), I opened one of the Powerlink cable terminals and switched the right and left conductors.
As it has been a while, please let us know your decision Noelke and your experiences.