I don't know about actual gains from it, but I deleted it on my 2001. The valve was damaged, so I just eliminated it rather than replace it. I use the wiring for a fuel pressure sensor now, so that is a plus as well.
It does get rid of that pipe sticking into the airflow in the intake port.
If I was getting a tune done for the rear O2s, I would go ahead and get rid of the EGR too.