Amp size for my Kicker Subs

Obviously you're going for SPL and not SQ. Are you putting these in a box with separate chambers? If so then get a 2 channel amp capable of putting out 500-600 watts RMS @ 4ohm per channel...or a mono amp that put out about 1200 watts RMS @ 2ohm if you're putting the subs in a single chamber...I personally prefer my subs in separate chambers.

Single or separate chambers mean nothing. Do not worry at all about your enclosure configuration, but DO worry about your enclosure VOLUME. It will determine DIRECTLY how much power your woofers will be able to handle - the larger the box, the lower the power handling. !!To a certain extent, this is true, but it is NOT the total answer, it will depend on the drivers!! Download a copy of WinISD, install it, learn it, and follow the recommendations for your woofers... Otherwise, like kklagge said, you will be looking for an amplifier that can provide 150 to 1200 total watts RMS into a 4 ohm stereo load (75-600 watts per channel @ 4 ohms - stereo woofers - one on each channel). This amp could ALSO be bridged to the same woofers, wired in series for an 8 ohm load (which is the same as 4 ohms per channel). You could also look for a mono amp that is rated 150 to 1200 watts RMS into 2 ohms (woofers parallelled).It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."