I've played it twice. Once we had to stop midway through for time constraints, the second time I was the traitor but had no way to win and lost very quickly.
From what I remember, there's an annoying amount of errata in it, and there's an issue where everyone should know the rules before the Haunt starts, because once combat gets involved it's hard to ask rules questions as the traitor without giving up information. From what I've heard from other people, it's fun until you run through a couple scenarios, and then it gets boring. It's not a game you win, it's a game you experience, and your mileage will depend on how interesting you think the scenarios are. If your strongest combat person becomes the traitor, you're pretty screwed.
I've played one other game similar to it called Space Alert. The premise is that you're a crew on a ship and aliens are attacking, and to win you need to fend them off. What makes it fun is that it plays in real time. There's an included MP3 that shouts out what's happening in 10 minutes of real time. In those minutes, everyone places commands to execute every time step, and the commands must stay face down. Once the 10 minutes are up, everyone reveals their commands, and you play out what happens. The design of the game is that different people need to coordinate because no one person has the time to do everything, but you have limited time to communicate and if any one person makes the wrong action, it can ruin the entire chain of events. Things like, you try to fire a gun but someone didn't charge it when you thought they would, so you don't damage that enemy and they got an attack you weren't expecting so your repair wasn't as effective as you hoped and that means this other gun is now offline and... (I don't actually know if that's something doable in the game, just making something up here that approximates how it feels.)