I agree with Sylver_Games and Ello. At my mind WED is still necessary to create BSP trees and to do the compilations of Light maps.

But after that I would do all the level design in GameEdit. You can see models better. You will see lighting of models better. You can better scale models. You will see shaders and terrain. You can place objects better on terrain. You can see stencil shadows, materials and maybe even your particles.

With that in mind there is quite a difference to WED. And I am looking forward to that. I hate all these work with compiling, running, exiting, changing, compiling, running and so on. I think you got my point.

Frank