Talking of subwoofers...

We have 2 PA's.

The small system - 2 full range cab's on poles.

The big system - Active crossover, 2 big amps, 15" Black Widow bass cabs with BOSE 802 flyers

The drummer hankers after changing the small system to "decent subwoofer and use the BOSEs". He could have a point; there's a distinct lack of bass coming back with the current "small" system, also you can't argue with the quality of the 802's.