They're similar, but different.
One thing I do like about Bububebes is that on the highest rise setting you can snap the inserts into the front of the nappy rather than the back, and the top insert covers up the row of snaps at the front - exposed snaps are my one complaint about our Goodmamas
. I think the Bububebes will probably fit slightly longer too. That said, I do love our turned & topstitched Goodmamas, and our plain OBV ones!