Well.....I used the swing and the bouncy seat the day I brought him home from the hospital....I believe he was 6lb. 8oz when we brought him home.
I wanted to take a nice bath, but didn't want to leave him, so I put him in the bouncy seat and brought it into the bathroom with me...I have been doing it every bath since then!
Then I used the swing because I was dieing to sleep in my bed on my belly now that my huge belly was gone
It was the only place at the time I was comfortable putting him in while we both napped. I swaddled him nicely in a blanket and put the swing on "low" .
I never thought twice about either of those.