They are garbage. Period. Those ones you listed a pair for 70 bucks . Very low end subs and I probably wouldn't see them last long. You can surely spend another hundred or so and actually get better subs for a little bit more money. Anything sold I n pairs in car audio subs wise stay away from. There's a reason the price is so low on a set of 2 subs.

Those r door speakers. I have some kicker door speakers they sound alright

door speakers or not. kicker is overpriced junk.

you can get a pair of sound ordinance speakers for lower than those kickers. and will sound much better.
although sound dampening your doors and sealing the speakers off will make crappy door speakers sound good.

i would suggest revamping your build just a little bit.. for what you listed your build was mediocre for 400+ bucks

spend another 100 or so and you can get much better

for headunit:

look for 4v outs, better power will give better SQ

this was the cheapest deck I could find on sonic that had 4v outs and I'm really happy with it.

ahh out of stock too bad

http://www.sonicelectronix.com/item_91191_Kenwood-eXcelon-KDC-X599.html

for speakers:

you're buying 2x or 4x?

Anyways, check these out, I liked the specs for the $ and it comes with free sound deadening, which as said above can really make a difference. Music sounds a lot better without the sheet metal in your doors reverberating

http://www.sonicelectronix.com/item_12266_JBL-P662.html


For amps:

class D amps are much better for subs and will produce less heat.

http://www.sonicelectronix.com/cat_i24_class-d-amplifiers.html



Was your plan to power 2 speakers off the amp and then bridge and power the sub?

Subwoofers (2):
http://www.soundqubed.com/HDS212_p_221.html

Amplifier:
http://www.amazon.com/AudioPipe-APCL15001D-Class-D-Audio-Amplifier/dp/B00BW54418

Wiring:
http://www.knukonceptz.com/mobile-audio/amp-installation-kits/sp/kca-complete-4-gauge-amplifier-installation-kit-/

Headunit:
http://www.crutchfield.com/S-URfj4DapWav/p_130X7600HD/Pioneer-DEH-X7600HD.html

Enclosure:
http://www.hifisoundconnection.com/Shop/Control/Product/fp/vpid/2816661/vpcsid/0/SFV/30046

Door Speakers:

http://www.amazon.com/Pioneer-TS-A1685R-Car-Speaker-Voies/dp/B00A0LYU2S/ref=sr_1_1?ie=UTF8&qid=1429546819&sr=8-1&keywords=Pioneer+4+way+6.5

Total comes to : $610 including shipping.
Install is on you though, and you wont have enough money for rear speakers but stockies should do fine for now.

Why do you think you need 2x 12's? Get a quality 10 inch dual vc sub (American Bass=$ or Sundown=$$$$) which sounds better than most 12's and still leaves you space.

Define sounds better