First, I have to ask if the subs are single voice coil, or double voice coil. Also, what brand of amps are you planning on running? If Polk, then I would subbst a 500.1 for each sub (regardless of SVC or DVC)... The SR woofers need a bit more power than the Momo woofers. I have both in different vehciles now.

A single 10" sub would be pleantly in the rear seat area.

hit me on PM if you want more ideas/information. Or call: 678-794-3697

John