Boy.....You are really talking about two completely different animals here. They are both nice speaker lines, so why do you want to switch?
The most obvious difference is the appearance. Other than that I would think the Martin Logan's are somewhat more transparent for 2 channel audio; and the B&W's have more power and dynamics for those movie soundtracks.
Since we are talking home theater, George Lucas uses Nautilus 802's in his studio, if that helps you decide. Lucas uses the Nautilus 802 for all surround channels (5).
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The most obvious difference is the appearance. Other than that I would think the Martin Logan's are somewhat more transparent for 2 channel audio; and the B&W's have more power and dynamics for those movie soundtracks.
Since we are talking home theater, George Lucas uses Nautilus 802's in his studio, if that helps you decide. Lucas uses the Nautilus 802 for all surround channels (5).
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