To use a bumber or not

Jessica • Having my first baby due on June 18
So my daughter will be 4 months on the 15 we finally got the crib because she's getting to big fort bassinet. Now our crib bedding came with bumber from pottery barn 
Now I'm having all these mixed feeling should I use the bumber or not
What are you guys doing
And also do u use a sleep sack of blanket? I don't know I'm so scared until she gets a little bigger but very scared of suffocation!