go to sonicelectronix.com, call the number at the top of the webpage and ask for Jeffrey. He is VERY knowledgable about all car audio. If he cant help you he will find someone that will. I bought 2 Earthquake Sound DBXI-12's from him and got an AWESOME deal on them. Put it this way, I didntv even pay 200 for both! You might even find a deal on replacement subs.
But to answer your question, the kit you posted is crap. I agree with Ty, looka nd see about getting a butyl surround as they will last longer. If not used that much, why not downgrade to maybe a single 10 with a matching amp.