I think they're pretty compatible with many SA cichlids if bigger than 10". I have 4 afrowana 5"-8" in a populated tank with 8 large indo dats, 1 7.5" NGT, 11" Red Eye Albino GG, and 51 clown loaches.
What they are not compatible with is intake from the filters (sand sifting studs these are!!!) and on occasion each other with the tail biting from the alpha.