What's the Scariest Haunted House attraction you have ever been to?

I have worked on a few really high end attractions for Halloween, but damn, I really need to get to Atlanta next year for Halloween, because apparently they take it to the next level.

http://www.adultswim.com/blog/gobble...pocalypse.html

http://www.atlantazombie.com/

I'm torn between Terror on Church Street in Orlando Fl or Nightmares in Niagara Falls, ON. The first one had amazing costumes and special effects. Nightmares is pitch black, but that's part of what's scary. Both use live actors. Both are hella fun.