Go for the MCP650. I've got a MCP350 and it's not that quiet. Two of them would be noisy.
You also don't need 2 x 3x120mm rads. 6 fans would kill you and a single 3x120mm will probably do the job, depending on the temperature of your room.
Make sure CPU is cooled first, then GPU.
Also, move the pump to the PSU compartment. Your case is ready for that and it should be more silent.