We personally just bought a dock a tot for my 6m old son because he stopped sleeping through the night since Christmas. I was desperate to get my sleep back! He’s been going to bed, awake in his crib since 2 weeks old so he’s “sleep trained” but if he wakes up at 1am he can’t self soothe and go back to bed without being nursed. I figured at this point if he somehow rolls out of the dock he will be able to keep his head up long enough for me to hear him from down the hall and I can fix his positioning. But within a week of using it he no longer wakes until I go get him in the morning to eat, and he’s never tried to get out of it! I really can’t see how they would get out of the dock and get wedged between the dock and the crib rail which is the company’s main reason for saying it’s not meant to go in the crib. We love that we can still use out AngelCare motion monitor too so if something were to happen and he started suffocating I would know within 10 seconds and could run in to help.