If you want to stay with rockford you can find better subs frum rockford, for not much more money. Just go to sum websites, and that amp is too big for the subs.
that amp would be the death of those subs, if you're set on those subs find a 2 channel amp that puts out 200rms @ (dont know your Voice coil configuration on em) or a mono amp thats about 400-500x1 rms @ (Xohms)......If you get the 500 just go easy on the Gain and dont crank up your bass boost from your headunit and you should be alright.