In Dominion, when someone plays a Torturer, I almost invariably choose to discard rather than take a curse. The exceptions are if I have a trasher (Chapel, Steward, Upgrade, etc.) that I have the actions to use anyway, or if I think there's a good chance a Masquerade will be played and I don't want to give away any cards. In the case of multiple Torturers (whether action-chaining or 3-4 players), unless it's happening every time I'll prefer to discard 4 cards and essentially lose a turn than add 2 curses to my deck.
I think the most common reason people take curses instead is they think their cards are too good to discard, but unless I am guaranteed a good turn (e.g. Village and 2 Torturers in hand, not relying on lucky draw), I'll choose to discard.
What is the value trade-off of discarding vs. taking a curse? How good of a hand do you need to take a curse? How do you evaluate the damage a curse does to your deck?
Of course, all Dominion games are subjective to the Kingdom Set. In a set with lots of ways to trash things, taking curses isn't so bad. I'm more interested in answers where trashing is harder, say a Remodel or Expand are the only options, or where +actions are hard to come by.