I would too suggest an air wrap or putting bubs in a sleeping bag if you have a prob with arm & legs hanging out. IMO it's just not worth the risk, they are a "no,no" for a reason. As for bumping, they will all do that, I think they get used to it or learn as Charlie is all over the cot too, but now that he's been like that for a while he doesn't wake up crying unless he's stuck in an odd position.