I personally prefer Millennium Force. It was my favorite coaster for 2 years, and, in 2012, it blew my mind. I was a pretty novice coaster enthusiast then who thought MF was the best coaster in the world. Although I've ridden better coasters now, it still remains one of my favorites because of what it meant to me then. I still think it is a great coaster, and, if I rode it today, it would likely still be in my top 5. Nitro is great, but I just prefer MF's slickness and laid back layout.