I have used a bumper for Jayden since he was about 7 or 8mths old as he was banging his head and waking and has had his leg caught really badly a few times. I think as long as they can move and get up themselves its ok, if a 2mth old rolled into it while its asleep it might not be able to roll back but once they are older I don't think its a real problem. If your worried about the pillow....I used to put the pillow under the bottom sheet so again they aren't going to smother themselves......I haven't used a doona we're in QLD so we don't have too much of a need as yet (although the blankets are on the bed already!).

Only do what you feel comfortable doing though.