Does the one supplied by CW do anything!?? For a nice and simple type of de-esser look at digitalfishphones spitfish. A simple device like that would be excellent for SFP.
Thats what I do as well at the moment (except I use a high-Q band-bass around 4KHz). But cant be used as an insert on a mixer, and makes the Window a bit messy by loading 2 devices to do one thing...