Did you get the pictures of my Fabtech kit?
Not a huge difference. Of course, I had the local muffler shop weld me up a custom setup so it may not be the "standards" of a pre-mandrel bent setup but the intake was actually somewhat noticeable. More so in the MPG's if you take it easy on the gas. I did notice a little more response in the throttle too. Hope this helps! Have you done any mods yet?