I was also looking at this amp, an Alpine PDX 1.1000. Here is the specs. Wouldn't this be a good amp for these subs?
mono subwoofer amplifier
1,000 watts RMS x 1 at 4 ohms (1,000 watts RMS x 1 at 2 ohms)
variable low-pass filter (50-200 Hz, 24 dB/octave)
Class-D amplifier design
stackable installation design with front-panel controls
quick-connect speaker connectors
preamp-level inputs and outputs
MOSFET power and output stages