I love my 4000's! I think that they sound great and are so elegant looking. Sure, the BL3's are fantastic, but they simply don't suit my interior...
Have you considered waiting for the new "tulip" subwoofer? I can't wait to see it! I will almost certainly get one. Where the BL2 visually seems to pair well with the BL3, I have my fingers crossed the tulip will match the elegance of the 4000's!