I am new to diesel performance on my truck, but just to clear things up for everyone, I have been working with a local diesel performance shop and quadzilla is BY FAR the best programmer available for the duramax. We have had my truck on the dyno testing different programmers and I think I can answser questions for many people. I thought EDGE was good...and it is, but we did not see the same performance gains as we did with the quadzilla stealth II. If you get the race version of the programmer ($300 more...), hang on. And you better have a heavy duty torque converter too. Banks needs to go back to the drawing board. We only saw a HP increase of ~20hp on level 6!!!! Whats the deal with that???? Bullydog was ok too....but nothing compared to Quadzilla Stealth II. They deserve a pat on the back. ~200hp at the rear wheels....programmer only....WOW