Agreed
#1. Drop the 3 amp idea and go for 1 or 2 MAX
look into kickers warhorse
or hifonics BXI Brutus class.. hifonics nicer amps are meant to be connected and play in a master/slave mode
and #2 Your subwoofers arent whats 1 OHM stable subs can play at any OHM "to an realistic extent" its the amplifier that has to be 1 OHM stable and normall i wouldnt suggest 1 OHM but with how much power your pushing any thing other than 1 ohm would be even more rediculously expensive that your already going for.
first off you dont need 3 amps to run a sub not sure the power of your sub like watts and rms wise but you only need 1 amp one strong enough to feed the sub its power it needs