how to get the best performance

Those are 4-ohm SVC speakers, and your amp is only stable at 4-ohms when bridged.  Your only option is to connect the woofers in series and operate in bridged mode at 8-ohms, which shuold deliver about 300 watts to the subs (150 watts each.)  Or connect each woofer to its own channel, which is the same thing as above but you'll have to make sure each channel is getting the exact same input signal.  Use a low-pass crossover set to around 100 Hz for these woofers.  If the amp or your crossover has a sub-sonic filter, turn it on.

another thing to set is your gain.  just turn your stereo up to about 3/4 of the way and turn your gain all the way down.  then slowly turn it up until you hear distortion.  then back it down just slightly and youre set.