I should say the original doom 3 is better because knowing that this game was short.
Here is the bad things I should say about this game. Some of the weapons are useless in a way like the grabber. Sure you use it in the beginning of the game but while you get better weapons you sort of forget that you do have a grabber. And the other thing that made me angry is that there's no chainsaw. THAT SUCKS!! Also when I was excited with the doom3 expansion I was reading previews that the graphics had improved. Well let me tell you one thing. They didnt't.
The good things I like or love about doom 3 expansion is that you get the new shotgun in the game. This weapon is awesome!!!And the other thing I like is the artifact. Its amazing that it gives you slow down time and 2 other power ups.
The things I said that were bad about doom 3 expansion doesn't mean it sucks. I thought it was worth the wait. If you love doom 3 then you might like the resurrection of evil, if you do have doom 3.