Thanks for the replies! Unless someone chimes in with something that changes my mind, I think I'll save my money for some other toy!
I'm not as critical of quality as I suspect some of the folks on Audiogon are. I've spent a relatively small amount of money getting a relatively good surround sound system and I'm happy with it. I just realized my Velodyne subwoofer is 17 years old and still going strong, which means my B&Ws are about the same age. If I haven't found a need to upgrade in 17 years, I don't see any reason to do it now, especially for a "slight difference". No need to fix what isn't broken!
I'm not as critical of quality as I suspect some of the folks on Audiogon are. I've spent a relatively small amount of money getting a relatively good surround sound system and I'm happy with it. I just realized my Velodyne subwoofer is 17 years old and still going strong, which means my B&Ws are about the same age. If I haven't found a need to upgrade in 17 years, I don't see any reason to do it now, especially for a "slight difference". No need to fix what isn't broken!