My first keyboard, and current one, is a Brown. I also bought the WASD sampler and was impressed with the feeling of the Red. Yes, the brown has a very slightly noticeable bump. I'm used to bottoming out, so I think I probably should have went with the red, since there's no bump feeling. I'm not a touch typist, so I don't care about the tactile feedback. I sort of regret getting browns, which one user advised that I shouldn't get, but got it anyway.
If you're a touch typist, or plan to be one, I'd say go with the browns, but if not, go with the reds.