It seems i have a slight passion for certain B&O products.
It must be the BL5s! I think it's interesting that you didn't put them all into the one 7.1 setup in the end ... Instead, it seems you placed them around the house to create listening/watching zones, right? Did you try 4 or 6 BL5s in the 7.1 setup prior to your decision to go for BL9s/BL3s as side/rear speakers instead?