Correct Power For Subwoofers?

I was thinking to buy 2 Fi BL 15"s and they are rated for 1000W RMS each. What I was wanting to know is if you think I should get two seperate 1000W RMS amps and wire each one to each amp, or get like a single 2500W RMS amp and wire both of the subs to the single amp for a 1ohm load? Please tell me what you think. Thanks!