I had a diablo for my '05 mustang GT. It was the most valuable tool I had. $300 and I was able to upload tunes to the car bought from online tuner shops (cheaper option than dyno, but dyno wouldve been better). So I had an 87 89 and 91 octane tune and seperate tunes for drag strip, street driving, road trip etc.

Also allowed me to log data for about a half hour that could then be uploaded to laptop and sent to an online tuner person.

Anyways, it was awesome. I would definately buy an srt-6 tuner.

I should point out it allowed the re-writing of the factory tune for if you need to go back to the dealer for anything.

I'm just typing this in case some people aren't sure what it does....