This farm spot seems fairly popular, you can get some really fast levels in the late 50s with it. It's also great for farming items.
I made a WD build specifically for this fight.
http://us.battle.net/d3/en/calculator...
This build seems fairly solid, gives you the right amount of survivability between SW, the heal from the totem and the heal from SH. If you have some more Vitality than I do you could probably use the 30% damage increase on the totem instead of the heal, which will help your group blow up the boss faster as well.
If you want to farm this spot it's really simple.
1. Change your quest to Act 4 quest 1.
2. Start game.
3. Open game to public whilst running to Tyrael to start the talk.
4. Kill boss and loot.
5. Teleport and leave game (it's faster to teleport than leave due to reduced log out timer).
6. Go back to step 1.