Fortunately, , I've never experienced "flatmates from hell". Once, when I was younger, I shared a flat with a friend for a couple of years, but we had no problems. We shared the housework and both paid the rent regularly. I think we both had good luck with each other because, although we'd been friends for a long time ago, that fact doesn't guarantee that the experience will work. Actually, we had similar habits and work schedules, so I'm sure that these circumstances contributed to a successful flat-sharing experience.
Definitively, I would NEVER go in for a competition like "House from Hell". I love too much my intimacy and my time to share it with strangers and being observed 24 hours a day.