My opinion of sim city 4 is that it is the best of the series. The new region mode is refreshing changes of play, Instead of having "faceless" neighbor cities you can over time, make a metropolis consisting of many small suburbs. I felt this concept was extremely well thought out by Maxis, because if you think of it, you now don't have to have large amounts of industry in your small city, as your Sim citizens will travel on your road system to neighboring cities to work.
I at first noticed I had problems with fires in my cities, as it turns out this is the games way of telling you that you don't have water to this area of the city, and that you don't have a fire station in the area. As for the other disasters Maxis gives the user total control of the disasters, you, the user is the only person able to call any disaster other than a fire.
If you are truly a fan of the Sim city series I am certain you can and will get enjoyment out this game.