I didn't use them. They block air flow. Another reason I didn't care for a bumper is because I had my sons bed in my room for a couple months and I couldn't see him. Bedding sets are waste of money IMO. Just buy a cute sheet!
I totally agree. They do block the air flow and make is hard for you to see your infant. Wonder Bumpers are a vertical crib bumper that actually let great air flow into your child's crib and create sound barriers as well. Many of the traditional bumpers have been a cause of SIDS, sometimes infants heads and limbs get caught in between the bumper and crib. Wonder Bumpers leave no room for injury at all because they are just pads that zip over the crib rails. I wouldn't use no bumpers at all, sometimes infants get stuck in the rails of the crib.