I thought you wanted different subs, not a new amp for the subs you have. And I doubt that particular hifonics amp will make much of an audible difference.
I doubt that you have $700 for subs because generally more expensive subs can handle more power, and you have to have money for a nice *** amp too. And to supply the amp you need an extra battery for sure and possibly a HO alternator. So unless you're a rich kid, $700 is way too much to spend on subs you want to use to piss people off at the local McDonalds.
But if you do want to have a loud *** system, you don't have to break the bank. Keep it under a grand. You've got a Cavalier, so put a big 15" in the trunk. I'd say a Fi BTL, DD 9515, or Audioque HD3 (like has been stated numerous times) and just underpower it, with a used IA 20.1 or Sundown SAZ-1500D. Then pick up a Kinetik HC1400 or HC1800 for the rear.
You'll probably be louder than you want to be. And you don't have to spend $700 on a sub or subs. So you can give me the extra monies to get me a **** alarm...//content.invisioncic.com/y282845/emoticons/fro.gif.c695f1f814b01c4ad99fe7f8cccadd29.gif