Two speakers with very similar graphs could still sound different, so numbers don't quite tell you the whole story unfortunately These two brands have different sounds, and even without hearing the two of them, I'd lean toward the B&Ws simply because more of the B&Ws I've heard in the same price ranges have been superior to Polk's offerings. I've owned Polk's former LSI speakers and even those I felt weren't as good as they could be. The one you've listed uses a newer version of the same tweeter, the Vifa ring radiator, and it was the highlight of the LSIs. Cabinets were excellent but the midrange was where an otherwise nice speaker stumbled. Polk's specs aren't quite detailed to tell enough about them. B&W offers plenty of info, so again, on specs alone, I'd have to give the nod to B&W. There's no reason not to provide that level of specs to the consumer, since each company definitely know exactly what those specs are. As I mentioned, that's only my opinion though.