Did exactly as it said it would
With having larger after market tires on the truck and checking my speed with my GPS, I was moving 4 MPH slower than my speedometer was reading. After a couple of programming attempts to dial in my tire size so my speedometer would match my GPS. I am very happy with the results. Now my truck runs a lot better, transmission shifts better, and PMG improved.
Couldn't really tell any difference on 87 octane but it did seem to come alive a bit on 93. Throttle response is definitely quicker though. I'd probably buy again just because I've heard bad things about the more expensive units on the market. Don't really think it helps gas mileage either. I do however have a CAI on the way & put exhaust on last month so we'll see how all the mods work together.