We are now in 2006. There has been a lot of research and educated reports on the 2003 and 2004 Cobra. The only difference in tunes from qualified tuners are the price of the tune, and whether you want an aggressive or safe tune with the air fuel ratio (i.e. leaning out the fuel or adding fuel and timing). Sutton now has a lot of experience and can give you whatever you need to run fast or go aggressive to please a client looking for that last once of HP. No one should run their Cobra in the aggressive mod riding around town. Tuners give you what you want for a price. The air density on the day of your tune, the air charge temperture, and the maxium boost is a major factor in your tune. If you live close to Sutton, use Sutton. You can always have them make adjustments if you want to be more aggessive. With the right equipment, you can learn to tune your own car but do you want to spend $5,000 to $15,000 for the right equipment? I keep a log on all of my runs and tunes from different tuners. I know what I am talking about when I say there is no big difference between Top Tuners other than being more aggressive with their tune. Being too aggressive is too risky.