How do I know whether to purchase a 2 ohm or 4 ohm subwoofer that is DVC?

Alright... I have a Pioneer Gm-D8400 Mono Class D Amp which has an output of 1200 Watts max, 300 watts x 1 at 4 ohms and 600 Watts max at 2 Ohms... I am going to purchase a Kicker L7 subwoofer and I would like to know if I should buy the Subwoofer as a 2 Ohm or a 4 ohm and do i wire the voice coils, there are 2 by the way, in a series or parallel? Thank you