I am a bit surprised by this. I am refilling 2 to 3 times per day and I was on 10 stinkys per day. I do like a big volume hit. Hey, I'm a big guy. But only one refill really surpizes me. I bought a second mini PT II just so I could have two flavors at a time. I'm still more than one refill on each per day. I'm not unhappy with the amount I use, but wonder what the big difference is?