The chute takes the coke to the 3rd floor, which is great if your vault is exactly where this one was, but there's a 2/3 chance that it actually makes it take longer. If you have the vault on the middle floor, you can break the first skylight and throw the coke down there, and if you have the vault in the large living room thing on the far side, bottom floor, you can throw the coke down the skylight in that room. So I don't buy the chute, because 2/3 of the time, it's useless.
Anyone who hasn't seen you yet (as long as the 'you're getting spotted!' bar isn't full / they don't have the red exclamation point over their heads) dies in 1 hit from any weapon or melee, regardless of what the weapon is or where you hit them. That pistol, for example, is just about the lowest damage piece of shit you can get - it takes about 2 full clips to kill a heavy swat (without headshots), but for stealth, it's fine. :)