The DT990 Premium are better in everything, I never need the clamp of the Pros on any headphone. I consider them the best deal for fun, immersive gaming. In Germany they cost like the Q701 and while the Q701 might be better suited for all music needs the DT990 600 is much better with entertainment like movies and games.
My T90 just arrived btw, will put them on later today. :D