the power handling on the polks is what? 250? the monos are 200wts and your receiver is 110? that would net 310 to the speaker, unless you never listen to your system over halfway (which im sure is unreasonable). you could use one mono amp and split it to run both woofers, however this would only work well for stereo sound seeing as youd have to make the fr and fl run into the amp. best bet for more power is to forget the onkyo fr/fl all together or get a stereo amp (which outlaw doesnt offer :-( ).