I bought several of what I had read were the smallest diaper covers when my son was in the NICU (he was born premature) and Prowraps newborns were one of the ones we tried.
I wasn't happy with them, and I did end up sending them back.
They were properly sized - they were just a little bit big for my boy when we came home (he was 6 pounds), but they probably would have fit a bigger newborn just fine.
However, the fit was just awkward. The leg holes were... weirdly shaped. I'm not sure how to describe it, but I just couldn't for the life of me get the diaper on my boy without it either being too tight or not tight enough. It was always just... awkward!
Also, there is this edging around the velcro tabs and they fold over and get stuck to the velcro... super annoying. Not only makes the velcro a little less useable, but they get all fuzzy and nasty looking super fast from being torn away from the velcro at every diaper change.
Anyhow, I only tried the newborn size, so I don't know if the other sizes fit better, but these just didn't work for us. I have a friend who swears by them, though, so I guess it's to each their own!!