We switched from the Merlin
We switched from the Merlin sleep sack because my baby was trying to roll onto her belly while wearing it at night but she wouldn’t sleep in a regular sleep sack. This thing is just tight enough around the arms but loose enough at the legs that she can feel comforted and still use her legs to roll. Also the arms keep her warm in the winter. Love this thing so much and already have recommended it to many other parents