Dont use Xbox to compare. Perhaps Doom 3 sacraficed more to go on xbox, so it runs better. Doom3 on xbox is so fuzzy, and out of focus. HL2 on xbox looks better than Doom3 on xbox, and only chugs where physics occur in a large amount. Doom's engine is not better. All it has is lighting indoors. Outdoors looks horrible. It barely has physics. Its a good game, but the overall imersion, and experience of Half-life 2 is 10 times more fun. Dooms gameplay is the same throughout the game. Monster comes out, tries to be scary, you kill him. Multiply that by 1000 and you have Doom. Games shouldnt rely on PURE graphics alone, and thats what Doom did. Dont get me wrong, I love doom (espically the shottie) but I think HL2 is better. (PS NEVER USE CONSOLES TO COMPARE GAMES THAT ARE PC PORTS!)