Is there any reason I can't use them to bi-amp the B&W's effectively giving them 360wpc?You can but (1) you will need some way to make sure that the gain of the two amps is identical so that the crossover balance is correct and (2) you will not have 360w available as the output will be limited by what the treble can handle and that will be <160 (assuming the HINT is driving the treble).
My interest lie in having the power to listen at lower volumes with clarity.It will not help you with this at all.