I would feel comfortable interchanging them. An EGR valve introduces the exhaust gases into the intake manifold(prior to combustion) in an effort to reduce emissions. I can't see any reason why the internal honeycomb or flow rate would differ to accomcodate this functionality. As Spook mentioned, expect fitment to be a minor hurdle tho. Any "universal" I have seen has been approx 4" too short and will require welding a small custom size piece on the rear of the cat to make it work.