Installed mine also----
I went over to Pasco and picked her up at the shop. Great place and even had "the Man" install it. I just recently installed a 4" SS Flowmaster from RIP, and an AFE Megacannon, so I'm not sure if I can really tell anything by the SOP. It runs better and seems to have more response, but since i put all these together in such a short time - who knows what did what. I am getting some slight better mileage. For example, I did an experiment where I completely filled her up - to the brim - ran a little over 100 miles, on the freeway (I-5 North of Vancouver to Kalama, Wa) - and here's the secret - DID NOT EXCEED 60 MPH!!!!!! I really tried to drive for mileage. I did use the cruise control - no dead throttle. This section of freeway is relatively flat, so no real grades to worry about. It was late at night - no traffic to speak of, no rain - dry - no wind. I went back to the same station and filled her back up to the brim - I achieved 22. 15! That's the best I've ever got - BUT, then again I haven't ever ran like that before. So I'm not sure what I would have achieved prior to my mods. I'm going to add some EDM's, maybe the 1. 0, or 1. 5's, as they are suppose to be better for fuel mileage. I'll duplicate the experiment to see if there's a difference.