I've had it since it first hit the market. The first time I used it, it was about 85 degrees out and about 2 o' clock in the afternoon. No spots, not a single one. Yes, you do have to go over the car with a sponge, wash mitt, rag, etc. It states that very clearly on the box. Then, you go slowly over with the auto dry deionized water. This part is kind of time comsuming, but make sure to get all parts of the car. Auto dry does not mean it dries fast, just that the water doesn't leave spots when it dries.
Also, I have found that using other brands of soap in conjunction with the auto dry feature is NOT effective. It's something about the makeup of the Mr. Clean soap that works along with the auto dry. I tried using Meguiars gold class soap, then auto drying, NO GOOD. Had to dry by hand.