I'm sorry, but running the game, and watching the game run in slow motion is a completely different thing.
Plus FYI with higher resolutions and AA the Tech 4 engine eats up the GPUs ram, and another thing I'd imagine my knowledge is pretty good seeing as I work in the games industry, so I have a pretty keen interest in game/tech related issues.
ID Tech 5 looks mega complex and awesome. Doom 4 and Rage. WANT!