Hi Andrew!
I was in the same dilemma i nthe winter holiday, then decided...and switched from FS2002 to 2004. I see now, I need some more memory, and cannot expect as much frame rates. Although I like the fact that it loads faster

Now I am struggling with installing those many add-on things to the new version, and having many problems, but I keep on trying.
I liked 2002 very much, but it is now 4 years old, and have some bugs that always annoyed me, and I cannot see those in 2004. So afterall, I think I was not disappointed.
And of course, IVAp works well with 2002, you only need more clicks to connect to the network.