Hi tibbs2
I have 4 Jawfishes in my 110 gal tank, no problem. They all dug their burrows in one corner of the tank and every once in a while they "visit" each others burrow. So far I can not see any difference between them, except for size. Have not observed any mating yet.
I also have 3 blue and 2 yellow assessors in the tank, no distinction between sexes. The blue ones have bread a few times, but always swallowed the fry after a few days.
Another great fish to keep in groups is the yellow wrasse, Halichoeres chrysus. I had 4 im my last tank and they are just great, constantly turning over the sand and always in motion, without bothering corals.
I really think most fishes are much better off in pairs, and I personally avoid a fish rather than keeping a single specimen.
Cheers
Jens