we've been using a sleeping bag for 3-4 weeks now i think. we never really wrapped corey - for one, i'm a terrible wrapper and he also seemed to get really hot & sweaty in a wrap. so we ended up just getting a grobag because they had such a good rep. he's had his best sleeps since we started using it. no idea whether that was the bag or a coincidence & him getting older, but i love it & he seems to as well. i also love that we can keep using them for ages rather than having to go through a de-swaddle process!