Allens tunes just flat out KICK ASS. And the service after the sale is better than any product ive bought!! Im not kidding , He has helped me retune my truck 3 or 4 times (I bought different MAF sensors and some drivability problems) and every time he retuned, called me to check the tune, and did not stop till i was satisfied. I wish everone did business like Allen does. Plus he can usually diagnose probs over the phone or suggest upgrades that will help your performance.I also tuned my truck with a hypertech PPG 3 that was cool, but didnt come close to his tune.