Exactly. 1200W is more than 600W, but @2ohm the amp is also producing significantly more THD (distortion). Distortion is what blows speakers, not wattage. That's why it is better to run a smaller amp with less distortion output, than a larger amp that puts out more distortion. You can use more of the power available on the smaller amp, as it can provide good clean sound.
I mention this, because the Kicker Solobaric Subs are DVC (Dual Voice Coil). This means you can wire them up in different impedences. This will dictate the operating impedence of the amplifier it is connected to.