Only one person is known to have survived the Killing Curse. We all know his name, so I don't think I have to write it here.

My favorites

1-Crucio <3<3
2-Imperio
3-Avada Kedavra

Definitely cruciatus curse, cause the pain can kill you, or drive you insane, while the imperius curse just lets you listen to someone other than yourself and the killing curse is painless. So definitely crucio.

All of them

I wuild prefer to be killed fastly by Avada, then get tortured to Death and lose my mind like the Longbottoms by Crucio.

Avada Kedavra is the worst one!

The pain of a "Crucio" may fade....but the emptiness never fades if a loved one is dead

Agree with KWcat_03x - Crucio would really hurt, but with Avada Kedavra, you would just die...
- don't like Imperio very much either, I know you can get away from it (Harry did in GOF), but it's still kind of creepy to be controlled like that :/

i'd rather be killed than be under the cruciatus curse. I don't know what it was about the way that the actors portrayed it in the films and the way Rowling explained it in the books I could just...feel it. The scene in Goblet of Fire when Voldemort did it to Harry and all I could remember was "It was pain" being the first sentence.

There's a much greater chance of you surviving Crucio even without ending up insane that the Avada. If I had to choose between the 2, I'd pick Crucio as there's a chance that I'll survive unscathed. Avada is final. Once cast you're dead.

and Avada Kedavra

i was stuck between this one and the imperio because even though crucio is painfull you can MAKE someone cut themself of something with imperio. though in the end crucio is worse

One word OUCH i wouldn't like to be under it.

It's just so inhumane. Avada Kedavra and you are suddenly dead. Crucio....crucio is a long and torturous death...

its just...horrible. thats all i can say.