Hi mate,
Both are PC Ports, so if you've played the PC versions they're exactly the same.
Quake2(x) is a suberb game on the PC, let alone the Xbox so you've gotta get it.
Haven't played DoomX yet, but the original PC was great.
Bit old now both of them. but hey!
You can also load the .WAD files from other DOOM games if you have them
drop me a line if you want me to send / up both for ya
