I bought this as I had read that swaddling was good to help tiny babies to sleep. However it has only been used a few times, and was an utter waste of money.
It is complicated to use, and if the baby is wriggling, almost impossible to wrap sufficiently tightly. It needs to be removed completely to change a nappy, which is a real nuisance in the middle of the night, as unwrapping it and then rewrapping is guaranteed to wake an otherwise sleepy baby.
We bought a Summer Infant Swaddle Pod (and bought a second one, once we realised how useless the Miracle Blanket was), which is far superior, and I would recommend buying the Swaddle Pod instead of this fiddly and overpriced item.