Dismal Rage / Opal Dark Briar

[Netherzul]

So...I'm camping an NPC for exp and it gives faction hits to these two.

Is there anything I should take note of for these factions before ruining them? Are there any essential areas for a Shaman that I will not have access to by ruining these factions? I've looked around and cannot find anything but I wanted to double check here first.

Thanks