It's only fun for maybe a few days, your car then does its adaptive learning thing and its back to square one. I mean yeah it does continues to feel "comparatively" more responsive from a dig than before. A good alternative to a tune if someone wants to preserve their warranty.
I'm tuned, so this is what I noticed:
1) it sort of fawked with my shift points. Car would take longer to downshift if I gave her gas. I know this because my tune is setup to downshift quick.
2) it made throttle response between 2000-2800 a touch laggy. But it was definitely more responsive from a dig.
Be better suited to a manual car in my opinion.