So i have a Diablo in-tune I-1000 from a previous car that is not married. I was told by diablo this would have some basic pre-loaded tunes. So I married it to the G8. Everything I have read on this forum and another G8 forum talks about the cortex 2950 being the best tuner for the G8GT. Some one please educate me on the difference between the two before I dump $350 for another tuner. I have the Diablo 91 Octane tune with Firm Shift tune installed currently. Thanks for your input and sorry for my ignorance. I came from back in the day of "tuned by frost" with a F-Body so I just shipped out my PCM and it was sent back to me. Now I have options to change parameters and am not certain on what all the parameters do.