[Sesobael]

My favorite cauldron grind is Gahrron's Withering. The mobs are tough, but it only takes 4 Ectoplasmic drops to get 25 rep, as opposed to 5 or 6 drops at the other sites. Also, the mobs drop more than enough money and runecloth to cover the cauldron hits.

It's rarely over-farmed due to the lethality of the ghosts, but a warlock should be able to take them 1 or 2 at a time and have minimal downtime.

I farm them with my voidwalker, DOTs and Life Drain to stay healthy. When the shadows get enraged, I Shadowburn, and that usually takes it down. When a spectre starts casting a spell, hit Shadow Ward to absorb the damage from the Mana Burn.

One last thing: most of the mobs at Gahrron's Withering drop Minion's Scourgestones, but the spectres drop Invader's Scourgestones. This increases the rep ratio a little bit and is nice.