I totally love the sound of the A-124 Wasp Filter module. It does have it's own special sound due to the special circuits in it which makes the module sound a little dirty and distorted. This can sound very nice with extreme filtersweeps, i often control the cut-off frequency with the pressure CV from the A-198 Ribbon Controller.
( middle position is notch )
One downside of the module is the lack of a QCV input like most A-100 filters have, so sadly the Resonance cannot be controlled via an external voltage. You can only adjust this manually.
It would have been nice if the Mix could also be controlled by CV... IMHO
Out of the box this filter can't go into self oscillation, in contrast to most of the other filters in the A-100 system, but modifying for self-oscillation is quite easy;
Soldering a 10k resistor in parallel to R13 (27k) leads to self-oscillation of the filter at the max. resonance setting of the resonance control.*
More info on this modification can be found HERE