I think it depends on the individual, like everything!

DD1 - she was wrapped until 11 weeks when she kept getting out of every wrap, even those 'miracle blanket' one's!! Yep, she got out of it.... you name it! She was so determined. Hated being wrapped.

DD2 - she likes being wrapped and yep, it's a sleep cue for her, just like the sling is I will keep doing it as long as it is working.... I have noticed her startle reflex isn't as strong as DD1's was though so her waking herself if she gets out of the wrap, has never been a prob