Do Corrupt Vessels turning into Thralls give more loot and XP?
Regarding XP:
Corrupt Vessel:
- Normal : 120
- Nightmare : 460
- Hell : 1300
- Inferno: 1600
Tormented Thrall:
- Normal : 120
- Nightmare : 460
- Hell : 1300
- Inferno: 1600
Regarding loot:
The thrall is of the same level as the vessel, so they have identical drop rates. Do keep in mind, however, that Tormented Thralls have a higher chance (75%) of dropping Health Globes than Corrupt Vessels (5%).
Source (Diablo III Brady Games Guide):
If a monster drops loot, the quality of the item(s) dropped is most affected by the monster's level. If the loot bursts from an environmental object like a chest or barrel or pile of bones, the type/quality of items is most affected by where you're at in the game.
Other factors can come into play, as well. The fact is, Diablo III monsters can drop a wide range of loot items, but the odds of a low-level monster dropping a high-quality item are extremely small. So overall, it works just as you'd expect: The higher a monster's level, the better chance that it drops good loot after you slay the beast.
No, you will not receive any bonus EXP or loot. All standard mobs have the same drop rates too.
As far as I know the droprate only differs by act and wether you kill champion packs/bosses or normal mobs. But all normal mobs have the same dropchance for items, so the Tormented Thralls do not have a higher droprate for better items.
Since bigger enemies most times give more XP you could wait until they transform, but you should be able to kill more of the Corrupt Vessels in less time so that the XP is not worth fighting those charging thralls, especially not in Inferno difficulty, they can be a pain in the a** ;-)