Hi Smokey:
180 watts would be the RMS or nominal rating. 300 watts would be peak. The unit features (4) 100 watt per channel internal Impedance Matching volume controls. Are you planning on only using two zones or four channels or four zones and eight channels. It takes two channels (left and right +/-) for a stereo zone. I am assuming you are utilizing eight channels and need the four zones. I believe the SSVC4 should be able to handle your application.
TL