No ever talks about this one, I think most people aren't even sure what it does. If you're like me, you tried it once, felt underwhelmed, and then forgot about it.
Here's the breakdown
Cost: 5 gold
Competes with Patches, Smuggler's Den, Bet on Boss, and Blackmarket
Removes all gold piles from the dungeon (average value for non-thieves is about 20 gold)
The packets are
A one-time 50% stoneskin effect OR a one-time +50% xp effect
15 gold OR 20 gold OR 25 gold
A random powerup
A partial healing effect (seems roughly equivalent to a health potion, not sure if it cures poison)
A trap that reduces mana to 0 and health to 1
This is an example of a preparation that is actually worse than taking nothing at all. The one-time buffs effects would be nice if you could control when you activate them, but you can't. Things like stoneskin, xp up, and healing are only really useful when you can plan around them. Given out at random, the are likely to just get wasted.
The gold comes out roughly equal on average, but I still consider this to be a net loss. Getting less gold hurts you more than getting bonus gold helps you. Moreover, there is a good chance that the gold chest will be in the last few squares of the dungeon, at which point buying stuff doesn't help you much anymore and you might as well have found zero gold instead.
The trap is completely unjustified. The prep is already a net loss, and the trap pushes it way over the edge.
The prep might be salvagable if the gold was even split among the chests, the trap was removed/replaced with a benefit, and the player was given the option to defer the effects of the boons until he needs them. It's still competing with superstars like Patches and Smuggler's Den but it would at least be a prep I would take every now and then.