I played the demo for this from a PC Gamer CD, and instantly fell in love.  I don't know what drew me toward this marvel, however at 10 am on the  release date, I was anxiously waiting outside my local software store.  I  enjoy the myriad of exotic weapons, the smooth level design, and especially  the level editor included on the second CD.  The Unreal Engine is extremely  flexible and a joy to work with, allowing me to dish out many interesting  effects.  About the only thing I do not like about the game is the enhanced  (instagib) shock rifle.  It's unimpressive, fires a half-second after you  hit the button (of course that might be the lag), and just doesn't do well  in combat.  About the only thing the that made the instagib rifle more  appealing was the Akimbo Instagib mod (which is availiable from a third  party programmer).