Hee. I tried those too and my son could have cared less whether it was a cool feeling or not. I had somewhat better luck with the Feels Wet liner ones...and if I recall the Pampers ones are better b/c the liner actually is separate from the absorbent part of the diaper. In the end though, I don't think it made that much difference in the potty training outcome. I am not ashamed to admit that we used bribery...I know some people use m&ms or something, but my son isn't a candy kid...he could care less if you were going to give him ice cream or candy.
We had a miserable frustrating potty training experience until I copied a friend of mine's technique. I went out and got a bunch of toys (nothing too big of a deal...some matchbox cars, watercolor paints, etc.) and wrapped them up so he couldn't see what they were. Each time he went in the potty he got to open a present. I had a couple of bigger presents for the first time he went pee in the potty without help, for the first time he made poo (that took a little longer). Also, it got to where he would just try to make the littlest squirt of pee just to get a present, so we started giving him a coin for his piggy bank for the little visits to the potty. Within a couple days he forgot to ask for the presents and he was going to the potty and not needing a pull up.
He still used a pull up at nap and at night for awhile. Eventually he told us he didn't want a pullup at nap, and then a few months after that, we accidentally ran out of pullups for night, and said, oh well, we'll try it. That was just about a month or so ago. He still has some accidents, but overall it's been pretty successful. I still had him wear pullups when he was sick, because cold medicine makes you have to go to the bathroom a lot.