'00 Buick Regal, supercharged 3.8L

Dear AquaTune,
I recently had one of your systems by you on my wife's '00 Buick Regal, supercharged 3.8L. My wife was totally dead against it when I first mentioned it to her, however, I did it anyway as a surprise gift for her. I used the excuse that I was going to do a tune-up on the vehicle while she was at work. She was rather suspicious being I don't normally work on the car. The next day she drove it to work and back and came in the house asking "what did you do to my car? It has never run so good." She also told me she had even burned the tires in taking off from an intersection. Then, and only then, did I tell what I had done and I asked her if she wanted me to take it off. She told me "No way!" Now for the kicker, after approximately one week, we calculated that she went from 28.5 mpg to 38.2 mpg. One and a half weeks after having hers installed, I had you come back out to install one on my '02 Buick Rendezvous, 3.4L at my wife's insistence!!! Hey, who am I to argue. Getting these twoAquaTunePlus kits, is one of the best investments I've made in a long time.
P.S.- The other vehicle is getting a 35% increase in mpg.