@allwyndlima: Well, if you've played with the original UT at a higher difficulty setting, and pretty much concentrated extensively on Morpheus, Hyperblast or anything in the Lightning DM rounds, UT2003 and UT2004 are a piece of cake.
I got my first introduction to UT on software rendering mode on a Celeron 400, and I haven't looked back since.
BTW, you definitely want to check out the Frag.Ops TC. Trust me on this one!
And oh, the one great thing about CS:CZ at the time was that they were bundling a HL2 preview CD with all the 10 gameplay videos that were released at that time.
One of the major influences for me getting that game.