I have no direct experience with those subs.. but.. from what i've read, they can hadle nice amount of power more then RMS, the 1200D isnt even giving them rated watts.
I'd get the 2200D tune it to 1500RMS for the first bit after a nice break in period I'd slowly tune it higher and if it starts getting stinky after long periods of play you know your reaching the mechanical limits. At that point back off the gain a bit and lower it some.
If you get the 1200D there going to be asking for more powa and your going to juice the gain, reach thermal limits and burn some VC's.
Better to have more power then not enough, as long as you have some commen sense!