I think, for the money, B&W is not worth what they offer in the 600 and 700 series. Yes, many think they sound good, even great, but if you look at the reviews with measurements you see a lot of issues in FR and Electrical Behavior.
Personally, I enjoyed my time with the Motion 60XT over the Motion 40, which blew the B&W 600 Series tower I heard out of the water.
Frankly, if you want better sounding speakers, look at Monitor Audio Silver 300 and 500 for Towers! Their bigger Center (Silver 350?) and Standmounts (Silver 100) are supposed to be very good, as well.