No game gives you this much creative freedom but technical issues dampen some of the enjoyment.
Upon release there were a lot of bugs in the code and some missing content. There were stability issues where the game would and sometimes still crashes. It is also a resource hog but the graphics are very clear and detailed. The Rush Hour expansion pack filled in the holes left by the original such as adding many more mass transit featuers like ferries, route query tools, more bridges, vehicle types as well as proper transitions of highways to roads.
There were 2 patches released for SC4, the last one being in 2004. Although they fixed the most serious technical problems, there has been almost zero official support from Maxis since then. It's prety sad that a 3rd party site like Simtropolis has to do all the work producing new bug fixes/mods/downloads for the game. They do this not just becasue they love Sim City, but due to the fact that there are some core design flaws with the original game released by Maxis.
For one, there is a problem with the demand cap preventing the highest commercial skyscrappers from developing, sims don't travel properly across your transportation networks making it very difficult to create region-wide cities that share resources. There is just a lot of frustrating random occurance in the game that make you wonder what is going on.
Despite 3rd party site's wonderful mod community, Maxis still hasn't made a random terrain generator for regions or cities. Instead they hobbled together a horribly laggy java applet online that uses real US terrain. I tried using it but after wasting 20 mins waiting for it to load a terrain that I liked I found that it only generates a city terrain, not for the whole region.
It's true that there is a good terraforming tool out there but it's a bit of a pain to install and nobody should have to go through a lot of work for a basic feature that should have been included with the product.
I may sound hard on this game but I'm only pointing out the flaws. Of course this is still the best city simulator you can find. The terrain editing tools in God mode allow you full control to shape the landscape to anything your imagination can come up with and you can create cities more realistic than ever before thanks to the detailed graphics and large variety of buildings. I also love how buidings can be constructed on slopes now which greatly adds to the realism.
If I had to rate this game during it's release, before any patches or mods I would only give it 7 but the mod community has really improved this game and evolved it into something much better than the original code Maxis released. Many mods are easy to install and will add many clever new features and fixes than you'll wonder why they were never part of the original and I highly suggest you to check them out. The scores for this review reflect the original product plus the 2 official patches since I cannot give credit to Maxis for content they did not produce.
Sim City 5 is in the works now and I'm very excited about that as I'm sure the rest of you are. We will have to really keep on the developers backs though to make sure they don't repeat the same mistakes again.