I'm personally not going to use one. I don't think the risk is worth it IMO. Maybe once baby is old enough to move around then I might consider putting one in, but I'm still undecided in that regards.
We didn't use one until our daughter was about 9 months old. We had way to many foot stuck between the rails in the middle of the night cry fests. I figure once they are rolling all over the place she would move before suffocating.
Re: Crib bumpers