SQ, the W3 will sound better, the W6/7's are mainly for SPL. The 2 12"s will play louder than one 13" as the cone displacement is greater. Buy the one amp its easier to tune than 2. I would really go listen to them and make the decision that way. Its a lot of money and you will have them for quite a while as subs last (as long as they arent abused).
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