I'm running the Cortex Superchips and i love it. I have it tune on 87 tune, which is the lowest and man my truck flys and i have a lift on 35" tires. I can smoke the tires for a while and they are E class tires so you can imagine how heavy my tires are. I still wanna try they other tunes but gas is a bit expensive so maybe when gas goes down. I might have to get rid of it maybe, since I'm in a tight situation but i hope not cause i love this tuner.
I am tracking so far that the superchips is looking good. Is there a tuner that improves performance along with incressing gas milage or at least keep it around what i get now. (15-20mpg) Might be a crazy question, worth a shot.