Apparently I’m missing something about HH. I would agree that it is a place one could farm tubby spiderants, but I wouldn’t call it a good place to do so, let alone “great” or “the best” (the latter is clearly the Dust, anyway).
The only spiderants I remember are in the section labeled “The Colony” on the loot map. That requires fighting through about half the map to get to, and while there were a decent number of spiderants it wasn’t anything special… Seems like roughly a wash with Frostburn if you just do the Hellfire-Neogenator farm route there (since Sully drops those two, that seems like the fairest comparison).
Are there more spiderants in HH that I’ve either forgotten or somehow didn’t run into when I’ve run it before?
Re: the original question, not really. I enjoy the Happy Couple fight, but sadly there’s no special drop there.