Now I’ve had a chance to use Paul-L’s de-esser it’s amazing :
if you select say 30 “frequency bands” it performs high-resolution de-essing …
SpitFish is not capable of acting with that precision.
[ BTW Paul-L’s De-Esser is not limited to sibilance frequencies, (i.e. those above 3kHz), so it could be used as a high-resolution multi-band compressor anywhere in the audio spectrum ].