Pro- They have a fancy logo that people think means something.

Con- People actually will buy a speaker just because it is THX certified, and in some cases wont even consider a speaker that is not. When infact most of the best speakers available arent THX certified. I like to say its because they dont need endorsements and logo's to sell their product, it speaks for itself.

probably not the answer you were looking for but in my mind thats basically what it boils down to.

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