It's not terror, it's just slightly annoying, but adds a few cool things to the game. It not being a cakewalk is a fairly rewarding change, not least because I know I'm getting the only gold trophy out of it, and a phat reward. Have no idea what it could be.
Also, despite playing for 16 or 17 hours I still haven't reached Vegas yet, or gambled. I don't have much interest in gambling much either, but we'll see. I want to find more quests to be honest. Currently the game, whilst obviously open world, feels a bit linear in the way it kind of shoehorns you on a path.