There is an article on the BB main site here

It has these guidelines at the end:

Safe Co-sleeping

  • Do not sleep with your baby if you are under the influence of any substance such as alcohol or medication (even if prescribed) that could induce a deeper sleep and reduce awareness of your baby (either partner).
  • Do not co-sleep if you are a smoker (either partner).
  • Sleep on a firm, flat surface (not a waterbed, couch or sofa).
  • Keep baby’s head uncovered and do not use doonas, to avoid overheating.
  • If you have long hair, tie it back, and consider that very large breasts or extreme obesity may reduce awareness of your baby’s position.
Hope that helps
I read in another thread that people found those insert things annoying and took up too much room.