does the ohm load matter how loud it would be...say if i had 600watts at 2 ohms or 600watts at 4 ohms. i know an amplifier would be more "reliable" at 4 ohms, but does the ohm load affect the subwoofers output?
If you have 600w @ 4 ohms, and a decent amount of space, then definitely the Tempest. If you have 600w @ 2 ohms (assuming you buy a 4 ohm DVC CVR), and less space, get the Kicker.
My friends got a tempest, it needs a pretty big box if you go ported. It will outdisplace the CVR and sound better as well. Depending on what impedance your amp puts out that power, how much space you can gather up,