Currently have two AB HD12s with 3kw of power.

I could squeeze 6-6.5 cubes net after port and woofer displacement in my trunk. Would I be better off with two of the new IDMAX 15V4s? They recommend 3 cube ported at 27hz per sub, so I could fit both. And with their 1200w RMS rating they should be ok on 3k.

Question is - is it worth it? Would they be louder and better SQ?