I don't know about the PacBrake, but, check out BD's website for their comparison to Banks. Basically, the dyno testing they did head-on with the new Banks brake showed that the Banks claims (which include "not interfering with the swirling flow near the turbo exit") appeared to be based on "theory" more than "proven fact". There was no measurable HP difference between the brakes in this test. (grain of salt - it's BD's website)
You can probably look at pictures of your Pacbrake, pictures of the BD, and figure if the same test helps ease your mind or not.
If you're seeing high EGT's, I'd say you need to open up your exhaust some. When I went to 4", with a BD brake added at the turbo outlet the same day, my "loaded" EGT's dropped about 200 degrees post turbo.