Sundown X15 Question

[Grimmjoww]

Well my Hx2 project is on hold while I wait for a custom voice coil lol. Now that I have a pretty decent amp I have some options. Never ran a 15 and want to try one. Is there any sub that moves as much air as the X15 but sounds better? I am looking for an spl monster that can daily, but I want it to move some air. I have heard an X15 in person so I am familar. Thanks