I went searching for a sleep sack that was well constructed and made of natural materials. I have been very happy with this one and have just purchased the same style the next size up. It opens completely flat for laying baby down, the snaps and zipper are good quality and easy to use, and it is very soft and cozy. The only possible improvement might be some kind of zippered vent along the bottom, for nights that are in-between temperatures, but I have never seen that on any product. Sleep has been a big issue in our house, and this has been one of a number of factors that have helped us improve our sleep situation, so thank you. It is very nice to hear our little guy say 'sleep!' and point at his sleep sack.