Updated:(Tyrael has been nerfed and chance of chest has been drastically reduced.)
So we've been doing a lot of act 2 nephalem buff farming with my buddies, but have found that a lot of people are just doing either act 2 Treasure Goblin farming, or act 3 Resplendent Chest/ Treasure Goblin Farming. We've tried both, and have had success with both. I do solo farm, but I know what works best for me there. The group I work with all runs with Magic Find (MF) and we're all just above 200MF (without nephalems), if that matters.
Finding and clearing a chest in act 3 can take anywhere from 2-8 minutes, while it only takes 2 minutes to find a loot goblin in act 2 (assuming that you have one in the game you join). We farm as a group so we can maximize the amount of goblins or chests we find, but there's some factors that make it unclear to me what really is the best bet.
While we can do treasure goblin runs faster, there are times when it seems like he wont spawn for 10 minutes for 4 people.
The Underbridge in act 3, had been up roughly 75% of the time for the 30-40 runs I did last night, but the chests only seem to spawn about 10-20% of the time inside. It's nice because act 3 can drop the highest loot tier, but it does take a little longer and we do suffer some deaths. Also my dps I run with has issues with clearing or finding chests since they're so squishy, but it's still doable for them. So I end up finding roughly 80% of the chests.
Just curious if anyones kept any tabs for a period of a few days as to the profits from each. Right now I've only farmed each for a day. I look forward to hearing your results or opinions.
Update: Tyrael has been nerfed, so if you can't do the damage yourself to clear any necessary mobs, or the elites if you like to kill them, then you will have issues. Tyraels damage has gone from 25k-40k a hit down to 1,200. At least from what I've experienced thus far.
Also the chance of the chest has been drastically reduced. As I have not seen any offical numbers on it, or any details of their stealth nerf of the chest runs, I can give you what I've seen from trying the run since the nerf, which is about a 10% chance for the chest to spawn. Unfortunately I've only been finding one or two chests an hour now, making the act 3 chest runs not worth it.
PS: Here's some good links that demonstrate these runs. Act 2 Loot Goblin and Act 3 Loot Goblin and Resplendent Chest.