I've been using Pampers almost exclusively on my 16 month old without issues. He wears a size 3 comfortably and will fit in a 4, though it will be a little big. I tried these for environmental reasons, but I am going to end up donating them and going back to the Pampers. The Pampers are much softer and fit him very well, while these are not nearly as soft and are bulky. I have noticed a stale urine smell when he wears these, and they don't fit quite right around the waistband.